Ashcroft GC55, Installation And Maintenance Instructions Manual

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WARNING! READ
BEFORE INSTALLATION
1. GENERAL:
A failure resulting in
injury or damage may be caused by excessive
overpressure, excessive vibration or pressure pulsation, excessive
instrument temperature, corrosion of the pressure containing parts, or
other misuse. Consult Ashcroft Inc., Stratford, Connecticut, USA before
installing if there are any questions or concerns.
2. OVERPRESSURE:
Pressure spikes in excess of the rated overpressure capability of the trans-
ducer may cause
irreversible electrical and/or mechanical damage to the
pressure measuring and containing elements.
Fluid hammer and surges can destroy any pressure transducer and must
always be avoided. A pressure snubber should be installed to eliminate the
damaging hammer effects. Fluid hammer occurs when a liquid flow is sudden-
ly stopped, as with quick closing solenoid valves. Surges occur when flow is
suddenly begun, as when a pump is turned on at full power or a valve is
quickly opened.
Liquid surges are particularly damaging to pressure transducers if the pipe is
originally empty. To avoid damaging surges, fluid lines should remain full (if
possible), pumps should be brought up to power slowly, and valves opened
slowly. To avoid damage from both fluid hammer and surges, a surge chamber
should be installed.
Symptoms of fluid hammer and surge's damaging effects:
• Pressure transducer exhibits an output at zero pressure (large zero offset).
• Pressure transducer output remains constant regardless of pressure
• In severe cases, there will be no output.
FREEZING:
Prohibit freezing of media in pressure port. Unit should be drained (mount in
vertical position with electrical termination upward) to prevent possible over-
pressure damage from frozen media.
3. STATIC ELECTRICAL CHARGES:
Any electrical device may be susceptible to damage when exposed to static
electrical charges. To avoid damage to the transducer observe the following:
• Ground the body of the transducer BEFORE making any electrical connections.
• When disconnecting, remove the ground LAST!
Note: The shield and drain wire in the cable (if supplied) is not connected to
the transducer body, and is not a suitable ground.
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