TWR Lighting E-1DB2, Manual

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M.E-2009.E-1DB2
3/25/07 – rev. 5/28/09
E-1DB2 CONTROLLER
3.6 BLEEDER CIRCUIT
The bleeder circuit is the most important safety item in this system. It consists of
resistor R32 connected to the high voltage storage capacitor through relay K2.
When the AC line voltage is turned off, the relay will close, allowing the resistors to
discharge the high voltage stored in the capacitor banks below 50V in 30 seconds.
It also has auxiliary bleeder resistor R33 connecting day capacitors directly.
**CAUTION**
NEVER RELY ON THIS CIRCUIT TO RENDER THIS SYSTEM HARMLESS. ANY
DEFECT IN THIS CIRCUIT COULD ALLOW A HAZARDOUS HIGH VOLTAGE
CHARGE TO REMAIN ON THE STORAGE CAPACITORS. ALWAYS WAIT AT
LEAST 30 SECONDS AFTER POWER HAS BEEN TURNED OFF BEFORE
STARTING ANY WORK ON THIS SYSTEM. ALWAYS MEASURE THE
VOLTAGE ON THE STORAGE CAPACITORS WITH A VOLTMETER BEFORE
STARTING ANY OTHER WORK ON THIS SYSTEM. NEVER ATTEMPT TO
DEFEAT THE SAFETY INTERLOCKS.
3.7 STROBE DIAGNOSTIC CIRCUITS
The diagnostic circuit is provided as a means of making system checks and
maintenance more convenient. This circuit is entirely contained on PCB #1, and
PCB #2. The circuits that are contained on PCB #1, and PCB #2 are as follows:
3.7.1 Control Power On
Line from the 120V AC input is sent through F2, safety switches CSS, BSS,
isolation transformer T2, and fuse f1 on PCB #1. Once this low voltage is at
PCB #1, it is rectified, and then sent to LED4 (D5). If, for any reason, power
is interrupted, (beacon opened, controller door open, blown fuses, failed
relay, etc.) LED4 would be extinguished.
3.7.2 High Voltage
The Cathode side of the high voltage HV is routed through a current limiting
resistor (R201). When the unit is in daymode, D14 will be at full brightness
when the capacitors are at full charge, but dims with the discharging of the
storage capacitors. A constant intensity indicates that high voltage is
present but capacitors are not discharging (check other indicators for fault).
When the red LED fails to glow, then the high voltage is no longer present.
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