Owner manual
  Page 11 of 13 
RD - 121 RACK MOUNT DIMMER 
 Version 1.2  OWNERS MANUAL      02/28/2005 
www.lightronics.com 
Lightronics Inc.            509 Central Drive, Virginia Beach, VA 23454           (757) 486-3588 
MAINTENANCE AND REPAIR 
TROUBLESHOOTING 
VERIFY THAT ALL POWER IS REMOVED FROM THE DIMMER BEFORE HANDLING THE UNIT. 
•  To simplify troubleshooting - reset the unit to provide a known set of conditions. 
•  Check that the console is powered and that console channels are correctly patched or set. 
•  Check the control cable between the dimmer and its console. 
•  Verify the loads and their connections. 
OWNER MAINTENANCE 
There are no user serviceable parts inside the unit. 
The best way to prolong the life of your unit is to keep is cool, clean, and dry. It is important that the cooling 
intake and exit vent holes are clean and unobstructed. 
Service by other than Lightronics authorized agents may void your warranty. 
OPERATING AND MAINTENANCE ASSISTANCE
If service is required, contact the dealer from whom you purchased the equipment or contact Lightronics, Service 
Department, 509 Central Drive, Virginia Beach, VA 23454 TEL 757 486 3588. 
Lightronics recommends that you record the serial number of your unit for future reference. 
SERIAL NUMBER 
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