Model 43-68, 43-68/1, 43-68/2 Gas Proportional Detector
Ludlum Measurements, Inc.
Page 5
February 2011
Flush
CAUTION:
The Model 43-68 uses double-end shut-off quick
connects. Both the male and female quick connects have to be
connected to allow counting gas to flow through the detector.
Connect output gas line from detector to output flowmeter.
Connect input and gas lines from main supply through the
regulator and input flow meter.
Turn main supply on and flush detector at 100-140 cc/min
or 10. 2 cm (4 in.) of water pressure at 1-2 psi gauge
pressure for 15 minutes.
NOTE:
A faster flush time can be realized if the output gas line
(only) is removed at the output flowmeter and the flow rate
maximized. Flush time may be reduced to 5 minutes. (Note that the
quick disconnect fitting should not be removed. With the fitting in
place, gas flows out the connection. With the fitting removed, a
check valve is actuated that prevents output flow.)
CAUTION:
The main supply should be reduced to less than 50
cc/min before the output gas line is reconnected.
After flush is complete, set flow to 30-50 cc/min.
Check output flowmeter. Determine detector leakage to be
less than 5 cc/min.
