WT.050.130.000.UA.IM.1108
ACUTEC
™
35 SYSTEM
37
Prior to calibration, remove the cover from the Sensor/Transmitter enclo-
sure and connect a DVM to the test points as shown in Figure 4.1. The
test points will provide a 0-1.00 Vdc signal proportional to transmitter
range. For example, a range of 0 to 10 ppm, 0 ppm is 0.00 volts and 10.0
ppm is 1.00 volts.
Figure 4.1 - Sensor/Transmitter Enclosure
NOTE: If alarm relays at the receiver are connected to devices that
should not be activated during calibration, place the receiver into
“alarm inhibit” as described in paragraph 3.3.5, Relay Inhibit, prior
to calibrating the Sensor/Transmitter.
4.5.1
Zero Adjustment (See Dwg. 50.130.150.001)
Before adjusting the zero, allow the sensor to fully stabilize by leaving it
on for approximately 12 hours. Ambient air must be “clean”.
The zero can be adjusted with just a DVM. Connect the meter to the test
points, and adjust the zero potentiometer until a stable value of 0.00
volts is obtained.
4.5.2
Transmitter Span (See Dwg. 50.130.150.001)
Before adjusting the span, the sensor must be fully stabilized and the
zero adjusted. See paragraph 4.5.1, Zero Adjustment.
If a Sensor/Transmitter is equipped with an Autotest Generator, it must
first be unscrewed from the sensor. The Calibration Adapter can then be
attached to the sensor.
The calibration gas is connected to the calibration adapter with an ap-
propriate tube. When used, gas generators must be allowed to stabilize
according to the manufacturer’s directions. Calibration gas is applied at
approximately 500 cc/min and should be allowed to flow to the sensor
for 10 minutes before adjusting the span.