Flash Technology FTB 312-3, Reference Manual

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FTB 312 and FTS 316 Revision13 — 02-20-2001 3-3
Mode Relay (K2):
24 VDC; 290 ohm coil
Discharge Relay (K3): 120 VAC; 290 ohm coil
Timing and Trigger Board (PCB1)
Replace this board with one known to be in good
condition. Note that the PCB1 board part num-
bers in this manual are either 24740xx or
24747xx. Call Customer Service for technical
assistance at 1-800-821-5825.
PCB1 part numbers vary. Be certain that you have
the number available, which is imprinted on your
board.
HV Rectifier Board (PCB2)
Replace this board with one known to be in good
condition.
Alarm Relay Board (PCB5) (PC 312-3AE)
Replace this circuit board with one known to be in
good condition.
Sense Module (PCB4)
Replace this circuit board with one known to be in
good condition.
Discharge Resistor (R1)
The measured resistance of this component
should be 35,000 ohms.
Burst Resistor (R2)
The measured resistance of this component
should be 250 ohms (two 500-ohm resistors in par-
allel)
Power Transformer (T1)
To test this transformer, first remove PCB1 and
PCB2. Apply power to the unit and measure sec-
ondary winding voltages at the terminals indi-
cated in Table 3-1.
Trigger Coupling Transformer (T3)
The coupling transformer should not have open
windings. An ohmmeter will indicate a shorted
winding because of wire size. check with an ohm-
meter at the wire terminals.
Red Light Module Components
Marker Relay (K5): 24 VDC; 450 ohm coil. Replace
the entire Red Light Module to replace the relay.
Marker Sense Transformer (T1 on PCB3): The
Marker Sense Transformer is mounted on PCB3.
If you suspect the transformer, replace the entire
Red Light Module.
Flashhead Component Testing
The following subsections describe component
testing for the components in the flashhead.
Flashtube (FT101)
Visually inspect the flashtube for broken elec-
trodes, cracked glass, and the solder connections
of the pins. A darkened envelope does not neces-
sarily mean the light output would be unaccept-
able. Before concluding that a faulty flashtube is
responsible for an inadequate flash, first rule out
other possible causes such as weak or absent dis-
charge voltage or triggering pulses.
Trigger Transformer (T101)
The resistance of the secondary winding (potted
assembly) should be approximately 150 ohms.
Check the ferrite core for cracks. Check the
mounting screws for tightness.
Trigger Coupling Transformer (T102)
The coupling transformer should not have open
windings. An ohmmeter will indicate a shorted
winding because of wire size. check with an ohm-
meter at the wire terminals.
Photocell Testing
The PEC 510 Photocell is wired directly to the
master power converter at TB1-1 and TB1-2.
1. Disconnect the photocell. The system should
go to nighttime operation.
2. Disconnect the master/slave interconnect line
on each power converter.
3. Operate the intensity control switch on each
power converter in turn.
4. If each power converter operates correctly
with the intensity control switch, the problem
Table 3-1 T1 Transformer Voltages
Terminals Voltage Range
TB3-1 to TB3-9 900-1050 volts AC*
PCB1 J5-8 to chassis 100-120 volts DC
PCB1 J3-1 to J3-2 22-26 volts AC
*
If this AC voltage is substantially below the specified
minimum value, check tuning capacitor C4.