RKI Instruments 65-2330RK - Manual (Page 8)

4 • 65-2330RK H
2
S Transmitter
Amplifier
The amplifier converts the electrical output from the sensor to a 4 to 20 mA signal that
corresponds to the detection range and transmits the signal to a gas monitoring controller.
A foam gasket that orients the amplifier and keeps it from rotating is installed on the
bottom of the amplifier. The amplifier includes the controller terminal strip, detector
terminal strip, zero pot, span pot, and test points (Figure 1).
Controller Terminal Strip
The interconnect terminal strip is a two position plug-in style terminal strip located at the
top edge of the amplifier. Use the controller terminal strip to connect the amplifier to a
controller.
Detector Terminal Strip
The detector terminal strip is a four-point plug-in style terminal strip near the bottom of
the amplifier. Use the detector terminal strip to connect the H
2
S detector to the amplifier.
NOTE: The H
2
S detector is factory-wired to the detector terminal strip. See the
Installation section of this manual for all wiring procedures related to the
transmitter.
Zero Pot
The zero pot is located in the upper left corner of the amplifier (see Figure 1). Use a small
flat blade screwdriver to turn the zero pot’s adjustment screw and adjust the amplifier’s
zero (H
2
S free) output during the start-up and calibration procedures. Turn the
adjustment screw clockwise to increase the zero output and counterclockwise to decrease
the zero output.
Span Pot
The span pot is located to the right of the zero pot (see Figure 1). Use a small flat blade
screwdriver to turn the span pot’s adjustment screw and adjust the amplifier’s response
output during the calibration procedure. Turn the adjustment screw clockwise to increase
the output and counterclockwise to decrease the output.
CAUTION: The third potentiometer is factory-set. Do not adjust it.
Test Points
The test points (red and black) are on the left side of the amplifier (see Figure 1). The test
points produce a 100 mV to 500 mV output that corresponds to the transmitter’s 4 to 20
mA output. Use the test points and a voltmeter to measure the transmitter’s output
during the start-up and calibration procedures. The black test point in the lower left
corner is the negative (-) test point and the red test point below the zero pot is the positive
(+) test point.
Junction Box
Use the junction box to install the H
2
S transmitter at a mounting site that is remote from
the controller. The junction box protects the amplifier and wiring connections made to the
amplifier. Use the top 3/4’’ conduit hub to connect wiring from the amplifier to the
controller. Use the cover on the front of the junction box to access the interior of the
junction box. Three spacers installed on the back of the junction box control the distance of
the junction box from a mounting surface and ensure that there is enough room to install a