RKI Instruments EAGLE 2 Manual - Manual (Page 209)

EAGLE 2 Operator’s Manual Maintenance • 199
Maintenance
The SO
2
and HCN ESM-01 sensors are the only ESM-01 sensors that include
user serviceable parts. This section includes a procedure for replacing an
ESM-01 sensor and for replacing the H
2
S scrubber in the SO
2
and HCN
sensors. When replacing a sensor, you may either replace it with another of
the same sensor or you may install a different ESM-01 sensor. If a different
one is installed, the EAGLE 2 will load the sensor parameters and configure
the ESM-01 channel for the new sensor.
Replacing the ESM-01 Sensor or Changing Sensor Type
1. Verify that the EAGLE 2 is off.
2. Place the EAGLE 2 upside down on a flat surface or hold it upside down.
3. Unscrew the three case screws until they disengage from the top case.
They are captive screws so they will not fall off of the bottom case.
4. Turn the EAGLE 2 right side up and carefully lift the top case away from
the bottom case. Be careful not to lift it so far that it pulls on the main
PCB with the cable that connects the top case to the main PCB.
5. Lay the top case down next to the bottom case to allow access to the flow
system.
6. Locate the ESM-01 sensor. It has a twelve wire cable with a connector
that mates to an ESM-01 sub PCB that is installed on the main PCB and
is normally located next to the pump. Figure 35 on page 180 shows an
ESM-01 sensor in a typical location.
7. Unscrew and remove the two screws that hold down the ESM-01 sensor
bracket.
8. Grasp the sensor firmly and pull it out of the ESM-01 flow chamber.
Rock it back and forth gently if necessary to pull it out. Take care not to
pull the cable from the sub PCB.
9. Rotate the locking lever counterclockwise on the cable connector that
mates to the ESM-01 sensor to unlock it.
10. Unplug the old ESM-01 sensor from the cable.
11. Connect the new ESM-01 sensor to the sensor cable and rotate the
locking lever clockwise to lock the connector.
12. Insert the sensor into the ESM-01 flow chamber and push it in until it
bottoms out.
13. Line up the holes in the ESM-01 sensor bracket with the two standoffs on