FAQ
Here you will find answers to many technical questions. If you can't find what you want, please contact us. We will be happy to help you.
This is not intended to be a complete reference for fixing equipment, although it may help fix common problems. Inexperienced personnel should never attempt repairs, nor does Dove Systems accept liability for attempts made in the field. Equipment that fails within the warranty period must be returned to the factory for repair, otherwise the warranty will be void.
Table of Contents
SceneMaster
How much power does it need?
Scenemasters require 2 sources of 120 volts AC at 20 amperes for full-power operation. The actual amount of power consumed is determined by the total wattage of the connected loads. Six 500 watt Fresnels require two inputs at 12 amps each. Six 750 watt Lekos require two inputs at 18 amps each. It is OK to load it with six 1000 watt PAR64 lamps, but you run the risk of tripping the building circuit breakers.
Why do the fuses blow or circuit breakers trip?
The fuses are directly in series with the outputs. Thus, only an overload in the output can blow the fuse or breaker. The Scenemaster cannot blow fuses by itself. Each fuse is associated with a pair of u-ground (Edison) receptacles. Check that the total load on the pair of receptacles does not exceed 1000 watts.
Why is a dimmer stuck on?
If a load has "failed on," especially after replacing a fuse, it is due to a shorted triac. The triac fails when a short in the output overloads it. The short can be in the cable, in the connectors, in the light fixture, or in the lamp itself. Although the fuse will blow, it is often not fast enough to save the triac, and it will need to be replaced. Most recent Scenemasters use a Q4015L5 tab triac. Early units use a T6421D studmount triac. The parts are available from Dove Systems. Please check your load by plugging it into a known good wall outlet before plugging it into other dimming channels.
Loads that dim normally but glow softly at the bottom end have had the dimmer idle come out of adjustment. This usually happens to three dimmers in a row but may be more noticeable in one fixture than another. The circuit card inside has trimmers labeled "idle" that can be adjusted to reduce the glow.
Why does the X scene work and the Y scene not?
The Scenemaster has a single crossfade slider located next to the grand master slider. Sometimes users mistake them for a pair of split crossfaders, grab both, and watch the lights fade to black in a crossfade to the Y scene. They do not realize that they are running down the grand master in addition to the crossfade. The crossfade timer must be set to zero if a timed fade is not desired. A failure of the internal circuit can also cause this problem and, if so, the unit will have to be repaired at the factory.
Why do channels 1-3 work but 4-6 don't?
Note that although only the upper motor base inlet need be connected to operate channels 1 through 3, BOTH inlets must be connected in order to operate channels 4 through 6.
How do I fade from the top row to the bottom row of outlets?
You don't. The layout of the Scenemaster Six has sometimes confused those unfamiliar with theatrical lighting control consoles. The output receptacles are wired together, forming six channels each with two receptacles per channel. The top row of six sliders is used to set a stage look for those six channels. The bottom row represents another look for the same six channels. One then fades from one look to another and back again, not from one set of lights to another set.
Why is the crossfade really slow?
The Scenemaster Six has a crossfade timer to allow a slow fade from scene to scene. Rotate the knob counterclockwise to stop this.
Why do a couple of channels flicker or wink out?
Broken slide controls will cause a channel to cut in or out. This can also occur if dirt, coffee, or some other liquid is spilled into the slide control slot. Curing this problem usually requires the replacement of the control. Preventing it requires covering the controller when not in use. Cleaning with WD 40 or TRI-FLOW may fix it temporarily.
I need triacs, fuses, fusecaps, or slide pot knobs. What do I ask for?
Current model Scenemasters (sold since about 1991) use what we call a "tab" triac. The part number is Q4015L6. Don't get hung up on the part number, though. Just ask for a tab triac. Older model Scenemasters use what we call a "stud" triac. The part number is T6421D.
The output fuses are ABC10 ceramic bodied 10 amp fuses. In a pinch, use a glass bodied fuse.
Not all Scenemasters have a replaceable fuse on the circuit card, but those that do have a 1/10 amp fuse.
The manufacturers of the fusecaps and holders have changed over the years. Simply ask for a fusecap, and you will get a complete fusecap and holder set. If you set out to find your own, use one that occupies a half-inch hole.
More recent Scenemasters have used a push to reset breaker that should not be necessary to replace. The sheetmetal has a .635 X .595D shaped hole.
What's that funny smell?
Dove products are odorless and the smell of smoke is an indication of a serious problem. Remove power from the product and have it repaired. In the Scenemaster product line, a short in an output load will sometimes burn a resistor associated with the channel.
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TechMaster & Sublime
What do the back panel switches do?
Although current model Techmasters do not, early model Techmasters had back panel switches. The switches on each Techmaster panel determine the DMX channel number for the first slider in each row on that panel. The switches are coded in binary: 1, 2 ,4, 8, 16, 32, 64, 128. Add the sum of the switches thrown to derive the channel number. (For instance, 1 plus 4 plus 8 equals 13.) The top row of the first panel is always one. The top row of each subsequent panel is twelve more than the top row of the previous panel. The bottom row of the first panel is twelve more than the top row of the last panel. The bottom row of each subsequent panel is twelve more than the bottom row of the previous panel. This is necessary to achieve single scene operation; the microcontroller knows to combine the rows for two scene operation.
TM-TS12: The top row is set for channel 1 (1). The bottom is set for channel 13 (1+4+8).
TM-TS24: Panel one top row is 1. Panel two top row is 13 (1+4+8). Panel one bottom row is 25 (1+8+16). Panel two bottom row is 37 (1+4+32).
TM-TS36: Panel one top row is 1. Panel two top row is 13 (1+4+8). Panel three top row is 25 (1+8+16). Panel one bottom row is 37 (1+4+32). Panel two bottom row is 49 (1+16+32). Panel three bottom row is 61 (1+4+8+16+32).
TM-TS48: Panel one top row is 1. Panel two top row is 13 (1+4+8). Panel three top row is 25 (1+8+16). Panel four top row is 37 (1+4+32). Panel one bottom row is 49 (1+16+32). Panel two bottom row is 61 (1+4+8+16+32). Panel three bottom row is 73 (1+8+64). Panel four bottom row is 85 (1+4+16+64).
Rental houses may team two or more Techmasters together to form larger consoles. Please contact the factory before attempting this.
How do I run a chase?
The console features a user programmable chase. In a chase, lamps are lit in sequence according to the chase program. The level of the chase can be set with the chase level control. If manual faders are set to light some lamps at a particular level, the chase piles on that level (the higher of the chase level or the channel level takes precedence). Note also that the chase level is affected by the grand master and blackout controls. In addition to the level of the chase, the speed of the chase can be varied with the front panel chase rate control. If either the chase rate or level is set to zero, the chase is suspended and will start again when the level and rate are above zero.
The chase includes three chase modes. These are forward (green LED), reverse (red LED), and build (yellow LED). Pressing the chase mode button switches from chase off to each of these modes. Forward executes the chase sequence in the order it was programmed. Reverse executes the chase in the reverse order it was programmed. Build executes the chase in the order it was programmed, but leaves each lamp on after it is brought up in the chase until the chase sequence is completed. Once the chase sequence is completed, all lamps in the chase go out. The chase builds bringing up more and more lamps, then they all go out.
To record a chase, set all channel sliders at zero (a chase cannot be recorded if a channel slider is not at zero). Press the chase record button (which then lights red). Press the bump button for each channel of the chase sequence in the order of the chase. Press the chase record button again (the red LED goes out). The chase has been recorded.
If you want a particular lamp to stay on longer than the others in the chase sequence, press that bump button twice during the chase record, recording that channel twice. If you want a pause in the chase where no lamps are on (assuming you are not in build mode), press the blackout button at the appropriate time in the chase.
If you accidentally press the chase record button, press it again (turning off the red LED). As long as no other buttons were hit in the chase record, the old recorded chase is maintained.
To restore the default chase (all channels in order), press the chase record button, then press the chase mode button. The default chase will be loaded and start executing.
A chase can include up to 255 steps. The chase is held in battery backed RAM that will maintain the recorded chase for ten years.
Why don't any controls work?
There should be at least one LED on at all times. If there is not, check the power supply (including the wall wart) to the controller. If the power checks out good, the console must be repaired.
Check the grandmaster slider and blackout switch then run up sliders on both rows.
Look for the status LED on the dimmer packs. Dove packs shine green with a valid DMX signal but red without one - in which case, lights don't come up. Check for proper setup at the dimmer packs, including the starting channel. An opto isolator or DMX terminator may help.
Why do a couple of channels flicker or wink out?
Broken slide controls will cause a channel to cut in or out. This can also occur if dirt, coffee, or some other liquid is spilled into the slide control slot. Curing this problem usually requires replacing the slider. Preventing it requires covering the controller between performances. Cleaning with WD-40 or TRI-FLOW may fix it temporarily. Due to the delicate nature of the circuit card, replacement of a broken slide control should be done only at the factory.
Erratic behavior on a block of twelve channels indicates a problem with a slave panel. Erratic behavior on all channels indicates a problem with the crossfade circuit card. The console should be returned to the factory for repair.
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IQ8 & IQ512M
Why do a couple of channels flicker or wink out?
Broken slide controls will cause a channel to cut in or out. This can also occur if dirt, coffee, or some other liquid is spilled into the slide control slot. Curing this problem usually requires replacing the slider. Preventing it requires covering the controller between performances. Cleaning with WD-40 or TRI-FLOW may fix it temporarily. Due to the tight spacing within the console and the delicate nature of the circuit card, replacement of the control should be done only at the factory.
IQ8 Specific
How do I set it up and test it?
The IQ8 outputs data for DMX channels 1 through 8. The starting channel selection switches on the dimmer packs must be set for this range. On the DimmerMaster 406 dimmer pack, the switches should be set to "001" for channels 1 through 4 and "005" for channels 5 through 8.
Adjust the grandmaster control to full (up position), both crossfaders to the up position, and the channel faders all down. As the channel one fader is adjusted up, the instrument plugged into dimmer one should come up.
How does it get its power?
The IQ8 may be powered either through the control cable (+12VDC on pin 5 of the XLR) or from an external power supply. There is a connector on the rear panel to accept a 2.1mm coax plug. The center pin is +12VDC. The outer shell is common.
The IQ8 may be connected to other types of DMX equipment (e.g. fog machines, strobes, and color changers) from different manufacturers. The IQ8 can be powered from pin 5 of the XLR. When this is done, it will be incompatible with DMX equipment that uses pin 5 for some special data use. Connector pinout functions are often screened on these products.
Why don't any channels work?
Check the power to the controller. If the dimmer packs do not supply +12VDC on pin 5 of the XLR, use an external power supply.
Check the starting channel address switches on the dimmer packs. DimmerMaster 406 dimmers should be set for "001" and "005".
Check that the controller is not in hold mode. The hold button has an LED that lights up in red while in hold mode. Move the crossfaders from the top of the slot to the bottom or vice versa.
How do I make it work like a two scene board?
Set the channel sliders to achieve the desired stage look.
Press the hold button.
Move the channel sliders to the levels for the second look.
Move the crossfade sliders from the up position to the down position.
Watch as the lights fade from the first look to the second look.
Press the hold button.
Move the channel sliders to the levels for the third look.
Move the crossfade sliders from the down position to the up position.
Watch as the lights fade from the second look to the third look.
Repeat as needed.
IQ512M Specific
What's the first thing I should try if it doesn't work right?
Reset the patch table to the default:
Simultaneously hold the right and left arrow keys to enter the menu.
The IQ512 ships with the password set to 000, so it may not ask for a password.
If a non-zero password has been set, you will need to key in the three digit password.
Press the down arrow key to get to "Load default patch table".
Press the right arrow key to select this option.
The display says "Confirm load default patch".
Press the right arrow key again.
The display shows its progress in restoring the default patch.
Press the left arrow key to leave the menu system.
Why don't any controls work?
There should be text visible in the display at all times. If there is not, check the power supply to the controller. If the power checks out good, the console must be repaired.
Run up the master slider, crossfaders, and all channel sliders. Run the crossfaders down and up again in case the unit was caught in hold mode. Try loading the default patch in case is was set incorrectly (see previous question).
Look for the status LED on the dimmer packs. Dove packs shine green with a valid DMX signal but red without one - in which case, lights don't come up. Check for proper setup at the dimmer packs, including the starting channel. An opto-isolator or DMX terminator may help.
How do I set the patch?
Simultaneously hold the right and left arrow keys to enter the menu.
The IQ512 ships with the password set to 000, so it may not ask for a password.
If a non-zero password has been set, you will need to key in the three digit password.
Press the down arrow key to get to "Edit Patch Table."
Press the right arrow key to select this option.
The display says "Patch dimmer @ channel @ level."
If you want to patch dimmers to channels, press the right arrow key.
If you want to patch channels to dimmers, press the down arrow key.
The display says "Patch channel @ dimmer @ level."
If you want to patch channels to dimmers, press the right arrow key.
Use the up and down keys to change the item being adjusted.
Use the right and left keys to change which item is being adjusted.
Hit the enter key to complete the patch assignment.
If you hit the left key when the ">" is already all the way to the left, you will exit the patch screen.
Press the up or down key until the display says "Save patch table."
Press the right arrow key to select this option.
The display says "Save to table 1."
Press the right arrow key to save to table 1 or bump buttons 1 through 9 to select another.
Press the right arrow key to save.
Press the left arrow key to exit this menu item.
Press the left arrow key to leave the menu system.
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House Light Controls
How do I wire the panels?
House Light panels may be bused (wired in parallel). One conductor for each control channel and three additional conductors (power, clear, and control common) are required. It is not necessary to hook the clear line to the dimmer pack, only to each panel. The panels require a source of +12 to +15VDC as a power supply. Dove dimmer packs offer this supply on the analog control connector. The control output is 0 to +10VDC.
What size wire do I use?
22 gauge cable is recommended.
How many conductors do I need?
One conductor for each control channel and three additional conductors (power, clear, and control common) are required. It is not necessary to hook the clear line to the dimmer pack, only to each panel.
Why do some panels fail to take or release control?
Usually this is a wiring problem but is occasionally a bad panel. The system can be tested by disconnecting the panels upstream of the one closest to the dimmers then adding panels one by one.
Why do some lights flicker?
Too many house light panels can load down the power supply from the dimmers. This causes it to fall out of regulation and produce a flicker. If you have several, try swapping in a "wall wart" type power supply with 120VAC input and 12VDC output, center pin positive, rated for 500mA or greater. They are available from the factory if one cannot be located locally.
Not all LED lights are compatible with phase-control dimming - even some that claim to be dimmable. Some will behave better with a small incandescent light in parallel with the LED.
A dirty slide pot can cause this, too.
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MPX-100 DMX Tester
Why did it stop working?
The batteries have died. The MPX-100 is turned off when the thumbwheel switch is set to 000. The unit is on if the thumbwheel is set to any other number. The right LED glows when the MPX-100 is on. It flashes when the battery is low and goes out when the battery is fully discharged.
The MPX-100 uses four AA cells. Alkaline batteries are recommended, though rechargeable nickel cadmium or nickel-metal hydride cells may be used. Rechargeable cells will not last as long due to their lower energy capacity and lower cell voltage. Batteries should be replaced if the power LED is flashing or will not light when the thumbwheel switch is set to a number other than 000. Batteries should also be removed if the unit is to be stored for an extended period of time (more than a month). To replace the batteries, remove the four screws holding the back on the unit. Replace the batteries, carefully noting the marked polarity. Replace the cover using the previously removed screws.
Why is the level flickering?
Broken slide controls will cause a channel to cut in or out. This can also occur if dirt, coffee, or some other liquid is spilled into the slide control slot. Curing this problem usually requires the replacement of the control. Preventing it requires covering the controller between performances. Cleaning with WD 40 or TRI-FLOW may fix it temporarily. Due to the tight spacing within the console and the delicate nature of the circuit card, replacement of the control should be done only at the factory.
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Shoebox Dimmers
including DM-406, DM-408, DM-410, & DM-124 (U-Ground & Stage Pin versions)
as well as DM-124-WM & DM-412-WM
How much power does it need?
The Shoebox requires 1 source of 120 volts AC at 15 to 30 amperes for full-power operation. Each shoebox is labeled with power input limits. The packs are designed to be as flexible as possible and may be loaded in a variety of combinations, provided that the load on any one channel and the total load on the pack do not exceed the limits marked on the pack itself. The actual amount of power consumed is determined by the total wattage of the connected loads. Four 500 Watt Fresnels at 100% require an input of 17 amps.
Think of the shoebox as similar to an outlet strip. The strip may be rated at 1500 Watts. Any one position in the strip may be rated at 1500 Watts. Loading all positions to 1500 Watts is likely to trip the breaker. It is not the outlet strip's fault.
What is a starting channel?
DMX control consoles send information for up to 512 dimmers at a time down one cable. The starting channel sets the pack to read information for a particular block of dimmers. The starting channel is set on a thumbwheel switch. When the switch reads 001, the dimmer pack runs on channels 1 through 4. Setting 005 runs on channels 5 through 8, setting 009 runs on channels 9 through 12, and so on. Valid addresses range from 001 to 509. The starting dimmer may be any channel, and dimmers on different packs can overlap some channels, though it is usually preferable to run them one dimmer per channel. It is not necessary to set the starting channels in sequence (i.e. 1-4, 5-8, 9-12).
Why is a dimmer stuck on?
If a load has "failed on", especially after resetting a breaker, it is due to a shorted triac. The triac fails when a short in the output overloads it. The short can be in the cable, in the connectors, in the light fixture, or in the lamp itself. The shoebox pack cannot short triacs on its own. Although the breaker will trip, it is often not fast enough to save the triac, and it will need to be replaced. With the exception of the DM-124, shoebox packs use Q4015L5 triacs. The parts are available through Dove Systems, but due to the very tight spacing inside, it is strongly recommended that the pack be returned to the factory for repair. Please check your load by plugging it into a known good wall outlet before plugging it into other dimming channels so you don't blow out more triacs with a bad load.
If all four dimmers are stuck on, the DIP switch may have been set to the emergency on function.
Why is there no output at all?
Check the signal present LED on the front panel. The LED should be lit at all times. If it is not lit, the shoebox pack is not receiving power. If the LED is red, it is not receiving a valid DMX signal or the thumbwheel switch is not set to a value from 001 to 512. A green LED indicates DMX is present. An amber (red and green) LED means the shoebox is on a 50Hz line or the pack is not receiving a valid DMX signal.
Why is this one dimmer pack but no others going crazy?
Occasionally the circuit card inside can fail or the DMX connection come loose, in which case the other dimmer packs in the system will continue to work while just one pack fails. Due to the very tight spacing inside, it is strongly recommended that the pack be returned to the factory for repair.
How do I test/use it without a controller?
The thumbwheel switch enables the load testing / local control function. The load test is useful for determining which load is plugged in, finding a burnt-out lamp, and putting light on stage when the controller is not plugged in. Set the first digit to 6. Set the second digit to the dimming channel (from 1 to 4). Set the third digit to the dimming level, from 0 (off) to 9 (full on). Levels thus set remain in effect until the power is disconnected. Here is an example:
Set the thumbwheel switch to 600. Leave the first digit at 6. Set the second digit to 1. Set the third digit to 5. The switch reads 615. The first load is at half power. Set the switch to 625. The second load is at half power, and the first remains at half. Set the switch to 639. The third load is at full power, and the first two remain at half. Unplug the pack and reset the switches.
Set the thumbwheel switch to 701 through 799 and the unit will perform a crossfading chase from 1 second (701) to 99 seconds (799). Example: Thumbwheel switch is set at 710. The unit will crossfade from channel 1 to channel 2 in 10 seconds. Then the unit will cross fade from channel 2 to channel 3 in 10 seconds, from 3 to 4 in 10 seconds, and then 4 back to channel 1. This will repeat until you change the thumbwheel setting or power down the unit.
The DIP switch sets individual channels for non-dim (full on or off) function or forces the output of all channels to full. In non-dim mode, the dimmer forces the load to full when it receives a DMX value of 128 or more (about halfway to full on the slider) and forces the load off when it receives a DMX value of 127 or less (about halfway or less on the slider). This mode is most useful for turning devices on and off that are not mains dimmable such as a fog machine, many florescent lights, or some LEDs. The emergency on function forces all outputs to full regardless of the control level.
Can I run it with LED fixtures?
Yes, many retrofit LED bulbs are dimmable, but be prepared to test multiple brands because even some LED bulbs that claim to be dimmable are not actually compatible with standard phase control dimming. Some bulbs have strange dimming curves or flicker at the low end of the dimming range. Low end issues can often be resolved by adding a small incandescent bulb or resistors in parallel with the LEDs. Dove Systems offers factory installed 4.7kΩ output resistors by special order or retrofit.
Can I run it with fluorescent fixtures?
Yes, the shoebox dimmer packs can dim fluorescents with "mains dimmable" ballasts. We recommend testing the dimmer with the fixture first. Some older ballasts have strange dimming curves or flicker at the low end of the dimming range. Shoeboxes may need modification to work with them.
Why has the power input connector melted?
Another common malfunction is damage to the power inlet or extension cord. The connector may overheat, causing visible damage (burn marks) or even fusing the power inlet to the extension cord. This failure is caused by a loose connection. This may be the screw holding the wire in the extension cord being loose, or may be a worn outlet on the extension cord. There should be a tight connection between the cord's outlet and the dimmer's inlet. If you can easily move the cord outlet once it is plugged into the inlet, then the cord's socket is excessively worn and needs to be replaced. Electrical current through a loose connection (either a worn outlet or loose connection in the outlet) will cause the connection to heat up causing damage to the inlet and outlet. Make sure the extension cord outlet fits the inlet tightly and that the screws in the outlet are tight.
The circuit breaker keeps tripping after an hour.
In some installations, a Shoebox’s breaker may trip after a long time in use. This is most likely to occur when a channel is loaded at or near its maximum rating and there are high ambient temperatures or limited ventilation. The solution will be to either decrease the load or improve cooling. Cooling can be improved by increasing the free space around the unit. They should never be installed in an enclosed space without plentiful free flowing air. If a better location or lesser load is not an option, one could try using a fan or switch to a higher capacity dimmer.
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Big Dimmers
How much power does it need?
Current Products
DM424-MD: single phase 120V 80A — which phase depends on configuration with its 24CFC
DM2412-WM: three phase 120V 80A or single phase (two leg) 120/240V 120A for full-power use.
Legacy Products
DM-1224: three phase 120/208V 80A or single phase (two leg) 120/240V 120A for full-power use.
DM-1212: three phase 120/208V 40A or single phase (two leg) 120/240V 60A for full-power use.
DM-624: three phase 120/208V 40A or single phase (two leg) 120/240V 60A for full-power use.
The actual power required is determined by the loads connected. Frequently a facility does not carry enough lighting instruments to load a dimmer system to full capacity. Sometimes a facility does not have power service of sufficient capacity to run a system at full power. Neither situation is a hindrance. If, for instance, a facility has only one dozen 500 watt Fresnel fixtures, the actual power required would be only three phase 20 amp! The power feed wire rating should match the circuit breaker ampacity, eg 50 amp breaker for #4AWG.
What if the building has single phase power?
Changing from three phase to single phase:
The power input connector is a terminal block. Each leg of the power feed connects to one terminal on the dimmer pack. These are marked "L1", "L2", and "L3". The neutral connection is made on the neutral bar, just to the left of the power block. The ground connection is made on the ground terminal, just to the right of the power block. When single phase (two leg) service is used switch S2, located near the center of the circuit board, must be moved from the "3 phase" position to the "1 phase" position. The power input terminal marked "L3" is not used. The two blue wires wrapped with red tape must be moved to the terminal marked "L1" and the two wrapped with black tape to "L2". The tiny blue wire stays in terminal "L3".
Note:
Single phase power will be about 240V measured from line to line.
Three phase power will be about 208V measured from line to line.
Line to Neutral should always be about 120V.
What is a starting channel?
DMX control consoles send information for up to 512 dimmers at a time down the same cable. The starting channel sets the pack to read information for a particular block of dimmers. The starting channel is set on a thumbwheel switch. When the switch reads 001, the dimmer pack runs on channels 1 through 4 (for a dimmer pack like the DM412-WM). Setting 013 runs on channels 13 through 36 (for a dimmer pack like the DM2412-WM). Valid addresses for a DM124-WM would range from 001 to 512 and from 001 to 498 for a DM2412-WM. The starting dimmer may be any channel, and dimmers on different packs can overlap some channels, though it is usually preferable to run them one dimmer per channel. It is not necessary to set the starting channels in sequence (i.e. 1-4, 5-8, 9-12, 13-16).
Why is a dimmer stuck on?
If a load has "failed on", especially after tripping a breaker, it is due to a shorted SSR (solid state relay module or "power cube"). The SSR fails when a short in the output overloads it. The short can be in the cable, in the connectors, in the light fixture, or in the lamp itself. The Dimmermaster cannot short SSR's on its own. Although the breaker will trip, it is often not fast enough to save the SSR, and it will need to be replaced. DimmerMasters use a Crouzet 84130271, Teledyne SSRD600240R40, Crydom D2440D-10, or other dual 40 amp non zero crossing SSR. The parts are available through several electronic distributors or from Dove Systems. Please check the load by plugging it into a known good wall outlet instead of damaging other dimming channels.
Loads that dim normally but glow softly at the bottom end have had the dimmer idle come out of adjustment. This usually happens to blocks of three dimmers in a row but may be more noticeable in one fixture than another. Some versions of the plug-in circuit card have trimmers labled "idle" that can be adjusted to reduce the glow.
How do I test it?
When the first digit of the thumbwheel switch reads "6", the pack is in load testing mode. The second and third digits show the dimmer being tested, from 1 to 24. The load test forces the output of the dimmer to full. This is helpful for focusing and troubleshooting. (e.g. Which channel is that? Is the lamp burnt out?)
Why do some or all channels work halfway, backwards, or with strange curves?
Incorrect power input phase settings or wiring can cause very strange behavior in blocks of one, two, four, and six channels. Check the phase switch on the plug-in circuit board.
Most often, the dimmer pack is wired in one of two power input configurations: three hots, one neutral, one ground (three phase); or two hots, one neutral, one ground (single phase) and switch S2, located near the center of the circuit board, moved to either the "3 phase" or the "1 phase" position. If the installer wishes to wire the pack with two legs of a three phase service, reserving the third leg for some other use, then the dimmer pack must be set for single phase use. The pack may even be wired to a single hot leg, in which case all three inputs are on the same phase and it doesn't matter how the switch is set.
The DimmerMaster is factory configured for three phase. Line to neutral voltage is always 120 volts. Line 1 to Line 2 voltage is 208 volts in three phase service and 240 volts in single phase service. It is very important that the input voltages be checked with a meter to insure that they are correct. A mistake can place 208 to 240 volts across a 120 volt lamp. The breakers will protect the unit but may not save the lamps. A double check of voltages before applying power can guard against such disaster.
Each leg of the power feed connects to one terminal on the dimmer pack. These are marked "L1", "L2", and "L3". The neutral connection is made on the neutral bar, just to the left of the power block. The ground connection is made on the ground terminal, just to the right of the power block.
When single phase service is used, switch S2 (located near the center of the board) must be moved from the "3 phase" position to the "1 phase" position. The power input terminal marked "L3" is not used. The two blue wires wrapped with red tape must be moved to the terminal marked "L1" and the two wrapped with black tape to "L2." The tiny blue wire stays in terminal "L3."
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MTX-DE 8 & 48
What is a starting channel?
DMX control consoles send information for up to 512 dimmers at a time down the same cable. The starting channel sets the decoder to read information for a particular block of dimmers. The starting channel is selected through a pushbutton switch on the front panel. Valid starting channels range from 001 to 505 for the DE8 and to 465 for the DE48. When the decoder controls the only dimmers in the system, the starting channel should be set for 001. Although decoder channels may overlap, it is usually desirable to arrange the system for one dimmer per channel.
How do you set it up for Brand X dimmers or LEDs?
Although there are ways to test the dimmers to determine the control voltage, there is no master list of manufacturers and protocols. Dove dimmers have always used 0 to +10VDC. Other manufacturers started with other standards, such as 0 to 15V or 2 to 7.6V. Some systems use 28V or even negative voltages. Thus, no quick and easy answer is possible. Try looking at the packs themselves (which often say) or in the system documentation.
Many standard LED power supplies support a 0-10V dimming feature making the MTX-DEs a great way to use LEDs with DMX.
Provided the console that is being replaced still works at all, remove the backshell from the low voltage control cable, locate the common terminal and a channel input, and run up the slider, reading the voltage range with a handheld meter. If the console does not work, try using a 9 volt battery to test the dimmers. Hook one terminal to the common input and the other to one of the channels. Reverse the terminals if nothing happens. If the dimmer comes up to about 90%, the pack is probably 0 to 10V. If it comes up to a little over half, the pack might be 15V. If it comes up to about a third, the pack might be 28V. Use the meter to check the polarity and determine that the voltage is not negative. Your favorite local theatre supply dealer (who often puts a nameplate on the dimmer rack or control console) may be able to help.
The MTX-DE is factory set for 0 to 10V output. Higher output voltages are possible: adjust R2 clockwise for voltage ranges up to 0 to +28V or 0 to -28V on negative voltage units. (Note that negative voltages require that the decoder be modified at the factory.) Throw DIP switch #2 and trim R2 for 2 to 7.6V.
Why did it suddenly quit working?
Sudden failures in previously functional systems frequently involve voltage spikes on the DMX input line to the decoder. Replacing the line receiver IC (MAX488 or 75179 in some older units) may repair it. If there is a recurrence, it may be necessary to install an opto isolator on the DMX line. Sometimes a voltage spike up one of the output lines blows several or all of the chips. Although a replacement chip set of all the IC's may be ordered, its availability does not guarantee a successful repair.
What if just a block of channels quit working?
A failure in one of the LM324 op amps may cause a block of four adjacent channels to stop working. A failure in one of the IC 4051's may cause a block of eight adjacent channels to stop working. The bad chip may be isolated by swapping chips on the circuit card.
Why do some channels dip and flicker?
When channels work on an individual basis but start to dip and flicker when more and more are brought up, the connection to control common is missing. This is a very common (no pun intended) problem when the decoder is being installed for the very first time or being moved from one venue to another. Each dimmer requires one control input of some voltage range, usually 0 to +10VDC. Each pack of dimmers requires a separate connection known as control common, against which the other control inputs are referenced. This connection is made between the dimmer packs and the terminals labeled "ground" or "common" on either side of the output terminals on the circuit card inside the decoder.
How do I stop the flickering?
Flickering is usually caused by improper DMX wiring. Do not split the DMX signal or attempt to combine two signals with a 1-into-2 adapter cable. Use one of the specialty devices from Doug Fleenor Design or Great American Market for this purpose.
Try setting the DMX termination switch. However, if there are more than one DMX devices on the chain, including decoders, fog machines, strobes, color changers, moving lights, and dimmers, check that termination has been set only on the last device in the chain. Termination at more than one device can cause flickering also.
Adding an opto isolator can fix signal problems. This device is available either as a standalone unit or as a factory modification to Dove decoders.
How do I test it?
The starting channel select switch has a load test / self test function. Setting the switch to 600 turns on all outputs at 20% of full scale (2 volts typical). Setting the thumbwheel to 601 turns output 1 on full with all other outputs off. 602 turns on output 2 while all others are off. This continues through 648.
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Control Cables & Connectors
How do I wire a DMX system?
All equipment should be connected in a chain with the controller at one end and the terminator at the other. It is important NOT to split the cable in two or more directions: this can cause signal reflections that will appear as flickering or non-functioning equipment. If the signal must be split, a specialty interface from Doug Fleenor Design will do it safely.
Dove Systems recommends that twisted pair, 120 ohm, shielded EIA485 cable of 22 to 24 gauge be used. Belden 8102, 8132, and 8162 are appropriate, but there are many others. All Dove equipment uses five pin XLR connectors as specified in the DMX-512 standard. Some manufacturers use three pin XLRs (in violation of the standard).
What is a terminator?
A terminator is a device to prevent signal reflections at the end of a DMX line. It soaks up the DMX signal at the end of the control run, mimicking a line of infinite length. It is important that termination be used only on one device, located at the end of the control line. Most Dove equipment includes a termination switch. If it is not present on your equipment, a terminating connector may be used. In a pinch, obtain a five pin male cable mount XLR connector and solder a resistor of between 90 and 120 ohms, 1/4 watt, between pins two and three. Plug it into the female DMX throughput connector on the last piece of equipment, at the end of the line.
What is an opto isolator?
An opto isolator is a device that breaks the electrical connection between two pieces of DMX equipment and retransmits the data down the line. It is used to resolve common mode noise or ground loop problems, to boost weak signals, and to protect against accidental damage due to high voltage on the control line.
How do I find out more about DMX?
Adam Bennette has written an excellent guide, titled Recommended Practice for DMX512.
How do I wire a DB15 / DB25 / Centronix 36 / DB50 (Analog, 0 to +10VDC)?
DB15:
pins 1-12 = channels 1-12
pin 13 = +15VDC (power supply from dimmer packs to passive controllers)
pin 14 = -15VDC (power supply from dimmer packs to passive controllers)
pin 15 = control common
This pinout is incompatible with Strand CD80 dimmer packs. See below for their special pinout.
Note that pins 13 and 14 are not required to be hooked up to active controllers, ie those with their own power supply.
DB25
pins 1-24 = channels 1-24
pin 25 = common
Centronix 36
pins 1-32 = channels 1-32
pins 33-36 = common
DB50
pins 1-48 = channels 1-48
pins 49&50 = common
How do I wire a 5 pin XLR (DMX)?
pin 1 = common
pin 2 = data not
pin 3 = data
pin 4 = (sometimes used as an optional second DMX output or in a talkback scheme or power supply)
pin 5 = (sometimes used as an optional second DMX output or in a talkback scheme or power supply)
The most common problem with these cables is that pins 2 and 3 are reversed. A quick and dirty way to verify cable wiring is to put a voltmeter between pins 1 and 2 or between pins 1 and 3. The digital signal can fool a meter into showing about 3.5V between pins 1 and 2 or 1.5V between pins 1 and 3.
How do I wire a 4 pin XLR (AMX)?
pin 1 = common
pin 2 = + clock
pin 3 = analog multiplex
pin 4 = - clock
See below for the special pinout for the mini connector sometimes found on Strand AMX equipment.
How do I wire a TY4F (Strand AMX)?
pin 1 = -clock
pin 2 = common
pin 3 = + clock
pin 4 = analog multiplex
The most common problem with AMX equipment is wiring an adapter from a 4 pin XLR to a TY4F.
How do I wire a 10 pin Cinch Jones (Analog, 0 to +10VDC)?
pins 1 - 6 = channels 1 - 6
pin 7 = spare
pin 8 = common
pin 9 = +15VDC (power supply from dimmer packs to passive controllers)
pin 10 = -15VDC (power supply from dimmer packs to passive controllers)
Note that pins 9 and 10 are not required to be hooked up to active controllers, ie those with their own power supply.
How do I wire an SRC (Teatronics, 0 to +10VDC)?
pins 1 - 11 = channels 1 - 11
pin 12 = +15VDC (power supply from dimmer packs to passive controllers)
pin 13 = -15VDC (power supply from dimmer packs to passive controllers)
pin 14 = N/C
pin 15 = common
pin 16 = channel 12
Note that pins 12 and 13 are not required to be hooked up to active controllers, ie those with their own power supply.
How do I wire a CD80 DB15 (Strand, 0 to +10VDC)?
pins 1 - 12 = channels 1 - 12
pin 13 = common
pin 14 = common
pin 15 = +12VDC (power supply from dimmer packs to passive controllers)
This pinout is incompatible with other dimmer packs. See above for the industry standard pinout.
Note that pin 15 is not required to be hooked up to active controllers, ie those with their own power supply.