HWH 680 Series Operator's Manual page 12

PREVOST H3-45 LEVEL FLOOR ROOM EXTENSION SEQUENCE
1. Ignition key must be in the "ON" position.
2. Park brake must be set.
3. Turn the room extension control panel key to "ON".
4. Any time the room extension key and ignition key is on, there
is a +12 signal to the air seal valve. The valve will open and
the air will exhaust from the seal.
5. After a 20 second delay, a ground signal will turn the amber
indicator light on the room extension control panel on. The room
extension will not operate until this light is on.
6. Push the Room Extension Control Switch to "RETRACT". This
will send a +12 signal for the pump relay, the room extension
solenoid valves, and the lock/unlock solenoid valves from the
control box. A +12 signal turns the red pump on light, on the
room control panel, on when the pump is running.
NOTE: The room control switch must be held in the "RETRACT"
position during the retract sequence. If the room control switch
is released before the sequence is complete, the sequence will
start over from Step 6 when the switch is pushed to retract again.
7. A +12 signal will open the room extend valve and the floor
down valve. The floor down valve will stay open during the com-
plete retract sequence.
8. When the floor is completely retracted, the floor down limit
switch arrangement will send a ground signal to the control
box. The sequence will not continue until the signal is
received by the control box.
NOTE: The room, floor and lock limit switches are not connect-
ed directly to the control box. The individual switches are con-
nected to a central limit switch indicator box for each room. When the
appropriate limit switches complete a +12 circuit for the limit
switch box, the limit switch box supplies a ground signal to the
control box so the sequence can continue.
9. When the floor down limit switch signal is received by the
control box, the room extend valve will close and a +12
signal will open the room unlock valve. This valve will stay
open during the complete retract sequence. This
assures the room lock pins stay retracted.
OPERATING PROCEDURES
ROOM RETRACT SEQUENCE
10. When the room lock pins are fully retracted, the room unlock
limit switch arrangement will send a ground signal to the control
box. The manifold pressure switch will send a ground signal
to the control box when pump pressure reaches 3000 psi. The
sequence will not continue until both signals are received by the
control box.
11. When both the room lock limit switches and the manifold pres-
sure switch signals are received by the control box, a +12 signal
will open the room retract solenoid valve. This valve stays open
until the room retract sequence is complete.
12. When the room is fully retracted, the room in limit switch
arrangement sends a ground signal to the control box. The
manifold pressure switch sends a ground signal to the control
box when pump pressure reaches 3000 psi. The sequence will
continue when both signals are received by the control box.
13. When both the room in limit switches and the manifold pres-
sure switch signals are received by the control box, the +12
signal to the room unlock valve is turned off and the unlock valve
closes.
14. A +12 signal opens the room lock valve.
15. When the room lock pins are fully extended, the room lock
limit switch arrangement sends a ground signal to the control
box. The manifold pressure switch sends a ground signal to the
control box when pump pressure reaches 3000 psi.
16. When both the room lock limit switches and the manifold
pressure switch signals are received by the control box, the pump
will shut off. All solenoid valves will close. The red pump on
light will shut off and the sequence is complete. The room control
switch may be released.
17. The air seal will inflate when the room control key switch
is turned off or if the ignition switch is turned off.
light on the room control panel will go out.
The amber
MP36.103B
13JUL00