Thermo Scientific 10519, Instruction Manual

Page: 24 / 44

Chapter 3 Operation
3-6
GAUGES
Three gauges are affixed to the front panel of the Model 200L Single Dilution Probe
Controller. These are vacuum, dilution air, and zero air (Figure 3-5). The dilution air
gauge should read from 30 to 45 psig with a dilution orifice setting of 100:1. A leak
check should be performed if this pressure is below 30 psig,. The vacuum gauge should
read from 17 to 22 inches Hg at sea level. The zero air gauge should be set to 20 psig.
Refer to the troubleshooting section for leak checking the instrument. The vacuum gauge
corresponds to the setting of the high pressure air adjustment for the selection of the
dilution orifice.
The span/zero rotometer, shown in Figure 2-1, should read 2.5 SCFH to indicated excess
flow of calibration gasses to the monitoring system.
Figure 3-5. Gauge Locations