Metrix 440 - Page 11

Doc# 90018-031 • REV L (April 2016) Page 11 of 16
The me that the vibraon amplitude must persist above a setpoint before the discrete out-
put changes state is individually adjustable for shutdown and alarm from 2 to 15 seconds.
To readjust the me delay, turn the shutdown setpoint (or alarm setpoint for alarm me
delay) knob CCW unl the LED illuminates. The me from this point to relay actuaon is
the me delay. Change the me delay via a nylon non-conducve screwdriver. Set CW to
increase me delay (one complete turn is approximately 0.5 seconds). Then, recheck and
readjust unl the desired me delay is achieved.
6.3 TestMode
The TEST posion of both shutdown and alarm setpoint adjustment knobs is used to test
the switch funcons without the need for vibraon. When the shutdown knob is turned to
TEST, the shutdown LED should illuminate and the discrete output should change state aer
the delay me (see secon 6.2) has elapsed. The alarm TEST posion (available only on DR
model switches) funcons in similar fashion, but has no eect on the 4-20 mA output.
6.4 AscertainingCurrentVibraonLevels
When the 4-20mA output is not being used with a strip chart recorder, PLC, or other log-
ging device, you can place an ammeter across this output and the current measured. 4mA
corresponds to zero vibraon and 20mA corresponds to full scale vibraon. Readings in
between these two extremes can be ascertained by scaling proporonately from 0% (4mA)
to 100% (20mA). Alternavely, the LED indicators for alarm (DR model only) or shutdown
(both SR and DR models) can be used. Since these LEDs acvate instantaneously (i.e., before
the adjustable me delay of secon 6.2), they can be used in a momentary fashion to check
the machine’s actual vibraon level. Slowly decrease the setpoint by turning the setpoint
adjustment knob counter-clockwise unl the corresponding LED illuminates. Note this set-
ng and quickly return the knob to its original seng (before me delay runs out). The level
at which the LED illuminates corresponds to the actual vibraon level.
NOTE: If the shutdown or alarm knob is moved
to the TEST posion but then returned to a nor-
mal seng before the duraon of the me delay
has elapsed, the LED will come on but the discrete
output (triac, FET, or relay) will not change state.
NOTE: For DR model switches where both shut-
down and alarm setpoints will be available, it is
recommended that the alarm setpoint adjustment
be used for this procedure instead of the shutdown
setpoint, to prevent an inadvertent machine trip.