Delta Faucet NANOTRACE DF-745 - Manual (Page 96)

92 Appendix B – Hydrogen Service Safety System
CAUTION
The operator is obligated to assure proper operation of the analyzer
air flow system as designed. Do not impede air flow at the inlet in
the front door or at the exhaust fan outlets on either side of the
cabinet in the rear.
NOTES
1 For hydrogen, which has a lower explosive limit (LEL) of 4%, the maximum allowable
influx in event of an internal leak would be 120 scfh, whereas the normal flow as defined in
the Operating Instruction Manual is about 1/10
th that at approximately 14 scfh.
2 Use of the analyzer case purge is at the customer’s discretion. It most likely is not
necessary since in the event of sample delivery interlock, the sample feed is blocked from
entering the chassis and the only open flow path through the system is dissipation of
remaining sample in the bypass, which would be vented externally, or in the event of an
internal leak, would be volumetrically insignificant.
3 The pneumatic control for the sample interlock and case purge valves is provided by an
internal 12 VDC solenoid.