malfunction. Refer to SECTION E, Driver Supply Regulator,
for additional information.
6.16
ColorStat™ panel Door Interlock
Refer to SECTION M, DC Regulator, for a simplified diagram
of the interlock circuitry. If a Door Interlock fault is indicated
check to make sure all doors are securely closed especially
where the plunger contacts the interlock switch itself.
6.16.1
Possible Causes
WARNING
ENSURE ALL POWER IS REMOVED FROM TRANSMITTER AND
THAT GROUNDING STICK HAS BEEN USED TO DISCHARGE
ANY RESIDUAL POTENTIAL WHERE POWER HAS BEEN AP-
PLIED BEFORE PERFORMING THE FOLLOWING STEPS.
6.16.1.1
Defective Interlock Switch
If the doors appear to be closing properly, remove all power and
ohmmeter each half of each switch for continuity when the
switch plunger is depressed.
6.16.1.2
deleted 03-01-96
deleted
6.16.1.3
Bad Connection at DC Regulator
Check the pullup resistors and interconnect wiring between the
DC Regulator and the Controller.
6.17
ColorStat™ panel External Interlock
Refer to SECTION M, DC Regulator, for a simplified interlock
diagram.
6.17.1
Possible Causes
6.17.1.1
External Interlock Terminals Open
If the external interlock feature was not utilized, a jumper should
be connected between TB1-1 and TB1-2. Ensure that the jumper
wire is properly connected. If a device requiring an external
interlock is connected to these terminals, (Phasor door inter-
lock, dummy load, etc.) make sure that this device is providing
closed contacts in the normal operating condition.
6.17.1.2
External Interlock Fuse F24
The external interlock terminals TB1-1 and TB1-2 are protected
by fuse F6 in the Center Control Compartment. Check the fuse
and replace if open. Make sure that there are no shorts on the
External interlock line.
6.17.1.3
External Interlock Relay K3
If F6 is good and the external interlock connections are
closed, verify that K3 is energized when the low voltage is
on and the external interlock is closed. If it is not, suspect an
open coil of K3.
6.17.1.4
DC Regulator Components
Check the components and interconnect wiring on the DC
Regulator.
6.18
ColorStat™ panel Air Interlock
Air interlock problems will be either intermittent, as could occur
if an air filter becomes blocked, or constant, as during a two or
more fan failures.
6.18.1
Possible causes
6.18.1.1
Fans Not Operating Properly, Failed/Running
Backward
The transmitter will turn ON for approximately 20 seconds with
NO air flow. Press the LOW power button and open the Center
Control Compartment door. A steady stream of air should be
felt coming from the holes in the interlocked inner door. If there
is little or no air flow, verify that the fans are operating in the
proper direction by placing a piece of paper on any of the filters.
If the fan rotation is correct, the paper will stick to the filter.
If the fan rotation is incorrect, refer to the fan rotation check in
SECTION II, Installation/Initial Turn-On.
6.18.1.2
Dirty Filters
Temporarily remove the air filters from the rear panel of the
Output Network Compartment. If the transmitter now operates
with the filters removed, clean or replace the filters.
6.18.1.3
Top Air Exhaust Restricted
If air is exhausted through air duct installed on the top of the
transmitter, a restriction can generate an Air Interlock. If an
exhaust restriction is suspected, operate the transmitter with the
Driver Compartment door open. Because the exhaust is no
longer going through the top, the transmitter should not incur
an Air interlock.
6.18.1.4
Rear Access Panel Open
The air system will not operate correctly with any rear access
panel open or partially open, due to the loss of air pressure in
the Driver Compartment.
6.18.1.5
Air Interlock Sensing Circuitry
The Air interlock sensing circuitry consists of U12, U13, U10
on the LED Board. Measure the DC voltage at J5-1 on the LED
Board. Depress the LOW power on button. If the voltage at this
point goes to approxi5 VDC and does not go LOW
before the transmitter turns OFF, then the air interlock switch is
operating and the LED Board circuitry is suspect. Refer to
SECTION Q, LED Board, for additional information.
6.18.1.6
Air Interlock Detector U17
If the logic LOW does not appear at J5-1 on the LED Board,
and all the above checks have been made, then the air interlock
detector U17 on the Driver Encoder/Temp Sense Board or
connecting circuitry is suspect. Refer to SECTION S, Driver
Encoder/Temp Sense Board for additional information.
6.19
ColorStat™ panel Oscillator Fault
NOTE
Use S1 on the LED Board while troubleshooting.
If the transmitter is incurring Underdrive faults, and the Oscil-
lator ColorStat™ panel LED is illuminated RED, the Oscillator
DX-25U
6-12
888-2297-002
Rev. R: 11-11-96
WARNING: Disconnect primary power prior to servicing.
