48 channel DMX dimmer pack (Version 2!) for LEDs and most
solid-state relays (SSR)
is for sale!
as of March 22 2011. A
limited quantity of used ones are available at a discount
price. See bottom of page for support information.
Board size: 3.5" x 4.0", with 4 holes for 6-32 screws; a set of 4
standoffs are provided. There are 3 holes at the
corners and one near the bottom right, at 2.49" x 0.16"
relative to lower left corner.
Feature set of new Version 2:
- 48 channels with one small board! No more
to not having as many channels as you really want.
- Each channel provides 20mA
(can be adjusted for 10 to 80mA - just ask) of
No external current limiting resistors needed. Hook up
LED(s) and go.
- Each channel can switch up to 15V,
wired in series per channel.
- 4096 levels of dimming
a pulse-width-modulation (PWM) refresh
rate of 1200Hz.
allows smooth fade up & down from black with no flicker
- LED brightness levels retained if DMX signal is lost.
- DMX ID settable 1-511 via DIP switch, changes are immediate,
status LED blinks orange to acknowledge
setting change. This is the starting DMX channel the board
responds to; for example, if the ID is 1, the board responds to
channels 1 through 49. If the ID is 49, the board responds
channels 49 through 97.
- DMX termination on/off via DIP switch. No jumpers or
to deal with.
- Test pattern via DIPswitch: fade up all channels to 100%, then
chase all channels, then repeat. Very handy
- High-resolution (16-bit DMX) mode yes/no via DIP switch.
- Multicolor status LED indicates DMX protocol or wiring error
(red), no DMX wire connection or no data on connection
(green slow blink), and valid DMX frames incoming (green fast
- Supports the top speed possible with DMX: 512 channel frames @
- LED connection headers are a unique "pluggable" design: they
from the board, wires added/removed, then plugged back in.
can be plugged in two ways: such that the wires exit up out of
board (shown in in picture) or more conventionally parallel to
board. This allows for much easier installation and for
installations, since the board and the LEDs are easily
- Board electronics runs from 6-15V DC @ 125mA with LEDs off and
protected. Contact me if 75% or more LEDs will be full on
than 30 seconds at a time and you are using more than 9V, as
thermal concerns. A
regulated power supply is suggested; cheap
"wall-wart" supplies typically output several volts higher than their
a garden-variety "12V" wall-wart may put out 15V or more.
may damage the board. Feel free to ask me about suitable
supplies or how to tell if yours will work safely.
- The DMX and DC power input have plated input holes on the
(in addition to the terminal blocks) to allow wires to be
the board if desired.
- 11 of these boards can be run from a single DMX source, so a
complete DMX universe of 512 channels can be easily built.
- For operating Solid-State Relays, please inquire.
digikey.com 365-1484-ND and 425-2402-5-ND are examples of SSRs
be directly switched.
(For existing customers looking for Version
1 information, go here).
Since this board is intended to be installed in an enclosure with
equipment, and wiring requirements are highly dependent on the
installation, there is
no case provided and the DMX connection is with a terminal block
of a bulky 3 or 5-pin XLR. See
wiring diagram below for details.
The basic operation is that this board switches the negative of your LEDs to
the power supply's ground. This is called low-side switching,
and is the most common way things like this are done, since it is
simpler, cheaper, and a little more efficient than switching the
positive of the LEDs (called high-side switching).
The wiring diagram is here.
Operation and testing:
- Turn off the LED power supply, and set the board DIPswitches
Hires OFF, Testmode OFF, Terminate OFF. Connect the power
to the board.
- Turn on the LED power supply. You should see the status LED blinking
green slowly. If not, check that at least 6V is
the (+) relative to the (-).
- Turn off the LED power supply, and wire a LED: the LED anode
to the power supply, and the LED cathode goes to the board, use
- Turn on the LED power supply. The status LED should
slow green. Now turn the Testmode to ON. Your LED should fade up to 100%,
then flash and go dark for a few seconds, and then repeat.
status LED blinks red/green rapidly. If your LED does not
check the wiring and the LED polarity.
- At this time, you're ready to
wire! I don't have a good solution for how to
the LED anodes (+) together; you can use multiple wire-nuts, or
multi-position terminal block and wire all its pins together, or
8" of wire and solder the LED anodes (+) to it. I've done
it all these ways and others. If you've got something
please let me know.
- I suggest wiring a half dozen or so channels and verifying
operation with the "Testmode" DIPswitch at this time.
- On to DMX: set the "Testmode" DIPswitch to OFF, choose the DMX
start ID (suggest 1) and set the
9-position DIPswitch for it (for help with decimal to binary go
the board. If you have a 3-pin or
5-pin DMX cable, you can cut the end and screw the three wires
terminal block or use a 3 or 5
pin to wire pigtails adapter - I normally have a few for
Either of the two DMX terminal blocks can be used, there are two
wiring convenience for multi-board installations.
- Flip the "Terminate" switch to ON, and plug into your DMX
and turn it on. The board status LED should be flashing
green. If it is red (meaning garbled data): the pin 2 /
pin 3 is
likely backwards or something is loose. If it is slow
seen; double check the wiring, that pin 2 / pin 3 / GND is
that your DMX source is outputting data.
- Now for the fun part:
the DMX start ID is 1, and your DMX source is outputting data
channel 1-48, you should be able to fade
down your installed LEDs. If there is a lot
of flicker, check the DMX wiring; if one wire is loose there
lots of bad data. If the fade up/down looks choppy,
with the fade up the Testmode does. Some lighting control
and software don't do smooth ramps; the fade up the Testmode
the board's best capabilities.
- DMX requires that the last (and only the last) DMX device in a
network be terminated; please look elsewhere for more details
this. The "Terminate" DIPswitch accomplishes this.
- The "Hires" DIPswitch is normally OFF. For finest
dimming control possible (such as from a computer) this can be
ON, and the board combines two DMX channels (8bits & 8bits)
create one 16-bit dimming channel so you can set the brightness
Discontinued March 22 2011. A
limited quantity of used ones are available at a discount price.
To my existing customers: thank you! I will provide consulting
& repairs as needed for the years to come. If you need one
two more for some reason, please inquire.
To potential new customers: unfortunately I am unable to
these at a cost that makes economic sense. If you have a
large-scale project that these or a variation of the design would
for (i.e. qty 25 or more), please contact me.
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