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installation
Open / Close on Alarm—The alarm and shutdown triacs (or analog switches)
are independently field settable for N.O. (close on alarm) or N.C. (open on
alarm). The switches are accessible with a non-conductive screwdriver via the
inner side panels.
Open on alarm is recommended in installations where triac lines are likely to be
noisy, e.g.: large transient voltage spikes due to unsuppressed relay, solenoid,
or other inductive loads.
Auto Reset Mode—In this mode, alarm and shutdown switches are automati-
cally reset to the non-alarm condition when the vibration level falls below the
set point.
Latch Mode—In this mode, alarm and shutdown switches remain “latched”
in alarm (shutdown) condition when the vibration level exceeds the set point
for the duration of the time delay. The unit is in this condition when the reset
terminal is connected to common.
Remote Reset Mode—When wired in this mode, the alarm and shutdown
switches latch in “trip”, but can be reset to the “non-alarm” mode by momen-
tarily interrupting the connection from terminal Reset to Common. This can be
accomplished with a normally closed momentary switch. The switch contacts
should be isolated from other circuits, potentials or grounds.
Remote reset is disabled if push-button reset option is selected.
20 Second Lockout (optional)—With this option, the shutdown and/or alarm
triacs will not be permitted to actuate for 20 seconds after Lock out is con-
nected to Common.
4-20 mA Output—This “self-powered” loop provides a 4-20 mA output current
proportional to vibration. For absolute option, 4mA = 0 vibration, 20mA = full
scale of the switches vibration range.
Special Considerations
Light Loads—The solid state triacs used in the standard 440 series are a
special high transient immunity, medium power type. Off state leakage is 1 mA
max and should not create any problems, even when interfaced with a load as
light as a programmable controller.
Minimum load required to keep the triac on is 20 mA typical and 50 mA max
due to the “holding current” specifications. If the load is less than this, a resis-
tor may have to be placed in parallel with the load, i.e.; for 115 VAC light load
Note