Metrix 440 - Page 8

Doc# 90018-031 • REV L (April 2016) Page 8 of 16
5.2.4 UnitswithElectromechanicalRelayOutputs(orderingoponsDand/orE=4)
Electromechanical relays are also available and represent the most exible type of output.
They are a good choice for a variety of applicaons. Consult Metrix product datasheet
1004730 for comprehensive specicaons pertaining to relay outputs.
5.2.5 Open/CloseonAlarm
The alarm and shutdown triacs (or analog switches) are independently eld seable
for N.O. (close on alarm) or N.C. (open on alarm). The switches are accessible with a
non-conducve screwdriver via the inner side panels. Open on alarm is recommended in
installaons where triac lines are likely to be noisy, i.e.: large transient voltage spikes due to
unsuppressed relay, solenoid or other inducve loads.
5.2.6 AutoResetMode
In this mode, alarm and shutdown switches are automacally reset to the non-alarm/non-
shutdown condion when the vibraon level falls below the set point.
5.2.7 Latch Mode
In this mode, alarm and shutdown switches remain “latched” in alarm (shutdown) condi-
on when the vibraon level exceeds the set point for the duraon of the me delay. The
unit is in this condion 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/non-shutdown” mode by momentarily interrupng the connecon from
terminal Reset to Common. This can be accomplished with a normally closed momentary
switch. The switch contacts should be isolated from other circuits, potenals or grounds.
5.2.8 20-SecondLockout(oponal)
With this opon, the shutdown and/or alarm triacs will not be permied to actuate for 20
seconds aer Lock out is connected to Common.
5.2.9 4-20 mA Output
This loop supplies its own 24Vdc power and provides a 4-20 mA output current propor-
onal to vibraon.
Most switches are supplied with ordering opon B=2 (absolute 4-20mA output reference)
where 4mA = no vibraon and 20mA = full scale vibraon (refer to product datasheet
1004730 for full scale range opons). A small number of older switches may use a B op-
on other than 2, designang an analog output that is proporonal to the setpoint rather
than the full-scale range. Consult the factory for addional informaon.
5.3 SpecialConsideraons
NOTE: Remote reset is disabled if
pushbuon reset opon is selected.
NOTE: Do NOT connect the 4-20mA output to an exter-
nal source of loop power as this may damage the switch.