Setting Relays For Latching Or Non-Latching Behavior; Setting Relays For Normally Energized Or Normally De-Energized Behavior - GE Bently Nevada 1900/27 Operation And Maintenance Manual

2.2.1 Setting Relays for Latching or Non-Latching Behavior

A latching relay stays in an alarm state even after the vibration has dropped
below the setpoint level for that relay. A non latching relay moves from its alarm
state to its non-alarm state once the vibration drops back below the setpoint level
for that relay. Table 2.1 describes how to set jumpers W7 and W8 to control
latching and non latching behavior for the Alert and Danger relays.
TABLE 2.1: Latching/Non-latching Jumper
Alert latching*
Alert nonlatching
Danger latching*
Danger nonlatching
* Factory default setting
2.2.2 Setting Relays for Normally Energized or Normally De-energized
Behavior
The Normally Energized/De-energized option controls whether power is applied to
the relay coil during an alarm state or during a non-alarm condition. For normally
de-energized relays, no power is applied to the relay coil during non-alarm
conditions. Power is applied during alarm conditions. For normally energized
relays, power is applied to the relay coil during non-alarm conditions. Power is
removed during alarm conditions. Normally energized relays are useful when you
want to shut a machine off when vibration monitoring stops due to loss of
monitor power. Table 2.2 shows how to set jumpers W5 and W6 for Normally De-
energized or Normally Energized Alert and Danger Relays.
Normally De-energized Jumper Settings
Alert Normally De-energized*
Alert Normally Energized
Danger Normally De-energized*
Danger Normally Energized
* Factory default setting
Settings
OPTION
TABLE 2.2: Normally Energized and
OPTION
Section 2 - Installation
JUMPER SETTING
install remove
W8
W8
W7
W7
JUMPER SETTING
install remove
W6
W6
W5
W5
7