XTBA DMX Network Module LM provides a simple and reliable method of multipoint DMX512. They are simple to install and use. The modules output is fully isolated and rebuffered from the input. The output is also line protected to prevent scroller power supplies etc. from getting back into the Output Module should they find their way onto the data line. In addition the LM Module also features output line monitoring displaying the state of the data line with or without data.

When mounting the Network Modules into the MK back box ensure that the earth screw terminal does not interfere with the modules mounting. On Output modules the earth terminal should be bottom left. The room inside the back box is tight, sorry about this as it might make wiring up the system tricky, but hopefully once installed you should not need to open the box again. When screwing the module plate onto the back box ensure there are no trapped cables as a shorted cable to case work will keep you ‘amused’ for hours tracking down the fault.

Each Network Module requires a DC voltage supply between 9 to 15 volts. Each module is locally regulated via the plastic tab voltage regulator - mounted off board to the metal work. Provision is also made for input reverse voltage protection by the use of a diode in the power supply feed to the 7805.  

Power consumption @ 15V

No connection on output or output unterminated =  55ma.

Connection on output and output terminated with 110 R across pins 2+3  =  85ma.

Module shorted pins 2 and 3  = 120ma.

DMX Data Input

Each Network Module has a receive value of 1 so a total of 32 units may be placed on any DMX branch. Further units may be added by using a network module as the last in line to re transmit data.

The DMX output is a isolated and buffered copy of the input. Up to 32 DMX receivers can be looped onto the output. The output is short circuit and over voltage protected. The last fixture in the line should be terminated.

Neither the data input or the data output are referenced to the case metal work. The input data Pin 1 (Screen/Common) is referenced to the PSU common. The output data Pin 1 is floating with reference to the input as it is isolated. The back box should be earthed as this supplies RF suppression to the unit and RF suppression for the DMX data. 

Connections: 5 Way Orange Klippon Connector

PIN 1(next to pillar / RHS) DATA INPUT SCREEN LOOP

PIN 2 DMX DATA IN MINUS LOOP

PIN 3 DATA IN PLUS LOOP

PIN 4 PSU COMMON LOOP

PIN 5(next to PCB edge) PSU PLUS 9-15 VOLTS IN LOOP

The leds on the Network Output Module LM display in the following way.

DATA – Green Led, displays valid DMX 512 data is on the input/output.

ERROR – Yellow Led, displays if the output line is double terminated being overloaded

INPUT POWER – Red Led, displays low voltage power

OVERLOAD -  Flashing Red Led, displays output line is shorted or overloaded

TERMINATED – Green Led, displays data line correct termination

The option switch is on the outside edge of the display PCB. If the option link is set towards the main PCB during installation all the led displays will blank if DMX channel 510 is at full all other channels are off for 30 seconds. To return the displays to on, channel 510 is held for 30 seconds all other channels off. The displays will be set to on after power up.

This feature is to allow modules in site of an audience to have their displays turned off during a performance from desk control.

The last output module in and branch should be terminated at the input connector with 100/120R resistor across data plus and data minus. This termination should prevent ringing on the line and prevent data loss or data clashes.

Supplied fitted into MK back box

Dimensions 85 x 85 x 45mm

Power 9 to 15V DC

Data DMX512 1986/1990

Pin Configuration Pin 1 Common, Pin 2 minus data, Pin 3 plus data.

Pins 4 and 5 are not connected

This product may only be used for controlling dimmers and moving lights. It must not be used in DMX512 applications for stage machinery or pyrotechnics. Using the product out of these specifications will remove all responsibility from the supplier.

ISSUE A 11/10/99

© XTBA 1999