Blue Bird TC/2000, Руководство пользователя

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4. System leak - check to make sure that the air pressure supplied to the solenoid valve or the diaphragm
is equal to 10 to 12 lbs. Again - CAUTION - not to exceed 12 lbs. of pressure is very important.
Excessive pressure will cause damage to the diaphragm and the solenoid valve.
5. Loose fasteners - same as above.
NOTE: Solenoid valves must be checked under pressure while activation of the electric solenoid is taking
place.
ELECTRIC STOP SIGNS AND CROSSING ARMS:
In order to troubleshoot an electric stop sign or crossing arm it is important to first understand how to
install the stop signs and crossing arms. The electric installation can be accomplished in two different man-
ners.
Example #1:
A. Dark blue to a switched 12V terminal. Red to a constant 12V terminal. Green to a proper ground.
This example would use the blue wire to activate the stop sign and to deactivate the stop sign.
Example #2:
B. Dark blue and red to a constant 12V terminal. Green to a grounded switched terminal. Example #2
would use the green wire or the ground to activate and deactivate the stop signs or crossing arms.
One of the major features of the electric stop signs and crossing arms is that all of the works are in the base.
You can troubleshoot the electric stop sign by first:
(A) Determining if the proper wiring installation has been achieved and that 12V and ground are avail-
able where required.
(B) Remove the rear cover of the base.
(C) Remove the red wire from the relay (wires lead to terminal on motor).
(D) Remove red wire from the limit switch.
(E) Replace the red wire on the limit switch with the red wire from the motor.
(F) With a battery charger or any other 12V source ground the motor terminal (black wire) and attach the
positive 12V to the red wire terminal on the motor. The motor should begin to activate and run
continuously until you remove the red wire.
(G) With a probe attached to the 12V positive side of the battery charger identify the black and light blue
leads on the limit switch at the motor base and with a 12V positive prove select either the black or the
light blue terminal and attach the probe to the lead of the limit switch. One of two conditions will
occur - either the motor will begin running or it will not. If the motor runs it should proceed until the
CAM circles and deactivates the limit switch causing the motor to stop. At that time switch terminals
with the limit switch to either the black or light blue depending on where you started and again the
motor should begin to run until the CAM positions itself to deactivate the limit switch. If both these
points prove to operate the motor then the limit switch, CAM and motor assembly are functioning. If
you have verified that you have the proper wiring installation as identified in the opening paragraph
then your problem rests with the relay. Replace the relay. This should render the sign operational
again.