SMC Networks 4011 Series Instruction Manual page 7

SIERRA MONITOR CORPORA TION
INSTRUCTION MANUAL
2.1.2.1 Alarm Adjustments
To change the alarm levels for Alarm 1 and
Alarm 2 first select the appropriate Alarm level to be
displayed using the SELECT button to step through the
choices available. Next loosen the two thumbscrews on
the front panel to remove the face plate. Alarm 1
adjustment potentiometer is in the bottom righthand
comer and above it is Alarm 2 adjustment potentiome¬
ter. Using a small jewelers screwdriver adjust the
respective potentiometer until display shows the re¬
quired setting. When Alarm adjustments are complete
replace front panel and change display back to CONC
(figure 2).
NOTE: There is a deliberate hysteresis built
into the alarm function to avoid oscillation when the
input (or 4-20mA Calibrator) remains close to the set
point. This hysteresis will cause the alarm to activate at
the set point and turn off at a slightly lower level than the
set point (or higher level if alarm level is programmed
to activate on the falling edge).
2.1.2.2 Alarm and Relay Configuration
Table 2 shows the positions for the jumpers to
be set for each alarm function. The default factory
settings are indicated. To change settings turn OFF all
power sources to the controller and unplug terminal
block. Remove the two screws in the upper side of the
rear clear panel and slide controller board out of the
case. Lift the jumpers using needle nose pliers and
remove/replace them as required.
Model Number: 4011 Single Channel 4-20 mA Controller
Page: 5