Replace O 2 Supply Switch; Checkout Procedure For O Supply Switch; Checkout Procedure For O - GE Aespire 7100 Technical Reference Manual

9 Repair Procedures
9.7.6 Replace O
2
Th e O
2
supply switch is located on the O
2
flowmete
r'
s regulator module.
supply swltch
1. Remove the upper rear panel (Section 9.2).
9.7.7 Checkout
procedure for O
2
supply swltch
Mll10140 08/07
2. Remove the two mounting screws from the O
2
supply switch.
AdJustment
screw
4.mmhex
3. Pull the O
2
supply switch out of the regulator manifold.
4. Install the replacement O
2
supply switch.
5. Tighten the screws.
6. Disconnect the leads from the old switch and reconnect them to the new switch.
7. Ad justthe alarm threshold forthe new O
2
supplyswitch
,
as explained in the
checkout procedure below (Section 9.7.7).
8. Replace the rear pane l.
9. Perform the checkout procedure (Section 3).
1. Remove the upper rear panel (Section 9.2).
2. Attach a gauge ωthe O
2
primary regulator test po 凡 (On pipeline only machines ,
attach the gauge
ωa
6-mm O
2
port).
3.
Adjust 由 e
O
2
flow control to minimum flow (clockwise).
4. Install an O
2
cylinder and open the cylinder valve (for pipeline only , connect O
2
pipeline source).
5. Turn the system on.
6. Close the cylinder valve (disconnect pipeline from source) and watch the test gauge
as the O
2
pressure bleeds down slowly.
Note: Th e "No O
2
pressure" alarm should occur between descending pre臼 ure of
221-193 kPa (32-28 psi).
7. If adjustment is required
,
set the adjustment screw so that the "No O
2
pressure"
alarm occurs at207 土 7 kPa (30 土 1 psi).
8. Disconnect the gauge and plug the test po眈
9. To reassemble , perform the previous steps in reverse order.
10.
Perform 由 e
checkout procedure (Section 3).
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