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Electronic Theatre Controls Inc

The Revolution Will Not Attempt to Home Upon Power-Up

This article applies to Revolutions made prior to summer 2005.  


After powering up the Revolution, the fixture will not home.  The red and green LED's on the upper enclosure flash.


The first thing to check in this situation is that the fan is running on the PWM (power module) in the upper enclosure of the fixture.  This is the module on the base of the fixture that does not have any outside connections.  Put your ear next to the ventilation holes and listen for the fan.  If the fan is not running, the PWM is bad.  The fixture should be taken to a service center to have the internal fuse checked and/or the PWM module be sent in for repair.  If the fan is running, the PWM is likely fine and the problem may then be in the low voltage data path within the fixture.  Remove any accessory modules and reboot the fixture.  If the fixture powers up, one of the modules most likely has a short in its 24V power rail.  This module should be sent to ETC for repair. 

This short typically occurs in an accessory module or on the wire harness going to the SCC (Secondary Control Card) in the head of the fixture.  If after removing all accessories, the problem persists, check the wiring harness to the SCC in the fixture.  If this is damaged, a replacement can be ordered from ETC.  If this is intact, the fixture's MCC (Master Control Card) is most likely damaged.  At this point, the fixture should be taken to a service center for repair.


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