1-23. DAYSIDE TEST BENCH 2A1 (cont)
(d) PMT controller 1A7 provides power to maintain the PMT at a constant
temperature (DRIVE AND DRIVE RTN).
(e) SENSOR-A and SENSOR-B lines inform the PMT controller of the PMT housing
(f) OVERHEAT-A and OVERHEAT-B lines inform the PMT controller of an overheat
condition in the PMT housing.
(g) AC FAN-A and AC FAN-B lines supply power to the cooling fan in the PMT
(7) Tray Assembly 2A1A1A9.
Tray assembly 2A1A1A9 normally is not contained in
the OSA, but is installed to test the high voltage power supply and pulse forming
(8) Relay Assembly 2A1A1A12. Relay assembly 2A1A1A12 (FO-14) contains four solid-
state relays (K1-K4) used to supply 115 vac 400-Hz 3-phase power to the UUTS. All
relays are energized by the same signal (+28 vdc) which is applied only when the OSA
access door is closed.
(a) Power of 115 vac 400-Hz 3-phase is supplied by the AN/USM-410 electronic
equipment test station at OSA connectors J2 and J4.
From connector J2, the power is
routed to relay K1 (input).
If the OSA access door is closed, relay K1 is energized
and the power is routed to connector J2 (TP) and to contacts of relay K2. Relay K2 is
energized (same time as relay K1) so power is routed to the indirect view display
There is one set of contacts in relay K2 that supplies +28 vdc to the OSA
(b) From connector J4, power is supplied to relay K3. Relay K3 energized
(same time as relay K1), so power is routed to contacts of relay K4 and to connector
Relay K4 is energized (same time as relay K1), so power is routed to tray
There is one set of contacts in relay K4 that applies a DOOR
INTERLOCK signal to the digital input of multiprogrammer assembly 2A2A6.
(9) Filter and Detector Assembly 2A1A1A14.
The filter and detector assembly
2A1A1A14 (FO-15) contains a relay and two microswitches (S1,S2) which control
the filter motor (M1). The motor rotates the filter 45 degrees to a position directly
in front of the PMT shutter.
Two optical switches (A1,A3) are used to inform the
computer of the lens position.
(a) During operation of the PMT, the OA FILTER 1 signal is
filter and detector assembly, and energizes relay K1. This action
through microswitch S1 contacts and relay K1 contacts (A3,A2) to
circuit is completed through another set of contacts (B2,B3) in
routed to the
routes +28 vdc
filter motor M1. the
relay K1, to ground,
and the motor moves the filter into the optic path.
When fully into the optic path,
switch S1 contacts open and motor M1 stops turning.
At this time, optical switch A1
transmits on OA FILTER POS 1 signal to the multiprogrammer assembly 2A2A6.