Bently Nevada 3300/46, Operation Manual

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0 Ramp Differential Expansion Monitor Maintenance
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84414-01
Test OK Limits [Cont]
6. Verify that the OK relay changes state (deenergized). Note:
all other channels in the rack must be OK or bypassed in
order for the relay to change state.
7. Decrease the power supply voltage (less negative) to -9
Vdc and verify that the OK LED comes back on and the OK
relay energizes (if the Nonlatching Not OK jumper is installed).
Press the RESET switch o n the System Monitor t o reset
latching Not OKs.
8. Gradually decrease t h e p o w e r supply voltage (less
negative) until the OK LED goes off (lower limit). Verify that
the lower OK limit i s within the lower OK voltage range
(reference Table 8).
9. Verify that the OK relay deenergizes.
10. W h e n finished, disconnect t h e p o w e r supply a n d
multimeter and reconnect COM and IN wiring to the channel
A terminals on the Signal Input Relay Module. Verify that the
OK LED comes o n a n d t h e O K relay energizes ( i f the
Nonlatching Not OK jumper is installed). Press the RESET
switch on the System Monitor to reset latching Not OKs.
11. Repeat steps 1 through 10 for Channel B.
TABLE 8. OK Voltage Limits
3 3 0 0 / 4 6
D I FFERENT I AL
EXPANSION MONITOR
..)ANCER S
6 . 0
..SEPT
B , PA S S
0
Transducer Type Lower OK Voltage Limits U p p e r OK Voltage Limits
11 mm
14 mm
25, a n d 50 mm
-3.25 Vdc to -3.35 Vdc
-1.65 Vdc to -1.75 Vdc
-1.30 Vdc to -1.40 Vdc
-19.68 Vdc to -19.88 Vdc
-18.20 Vdc to -18.40 Vdc
-12.40 Vdc to -12.60 Vdc
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