Computer Weld GTFM IV, Руководство по эксплуатации и установке

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2.0 Installation
2.1 Options
The GTFM can be used as a portable or in-line gas flow monitor. If the unit was
purchased as a portable monitor, it will be equipped with a rubber gas cone. The
cone is designed to fit standard torch gas cups and allows the GTFM to measure the
actual gas flow at the torch. To install, simply press the GTFM gas cone onto the
welding torch gas cup. Make sure that the cone is fitted snugly to the gas cup.
2.2 Gas Line Hookup
The GTFM may also be installed into the gas line and used to permanently monitor
the gas-flow rate. This model is supplied with barbed 3/8 ID hose fittings. The sensor
will accept any 3/8” NPT pipefitting. The user may hard plumb the sensor if desired.
DO NOT USE PIPE DOPE OR TEFLON TAPE ON THE PIPE FITTINGS . The
sensor should be located between the welding-gas solenoid and the torch. DO NOT
INSTALL THE SENSOR ON THE INLET SIDE OF THE GAS SOLENOID . If the
sensor is installed on the inlet pressure side of the gas solenoid, the maximum
operating pressure (50 psi) of the transducer may be exceeded.
WARNING : Do not over tighten fittings as it may twist the sensor out of position .
2.3 Cable Hookup
The GTFM provides an analog voltage, which will represent gas flow. This analog
voltage can be monitored by using the Auxiliary Cable and connecting the plug to the
"AUX" connector on the bottom panel. The output voltage will have the following
relationship:
2.55 volts = 255 cfh
or
.01 volts/cfh
The output impedance of this signal is 100 ohms and can source 2 milliamps of
current. The analog-interface cable can also be used to supply power to the GTFM.
The power requirement is (10 - 28) vdc @ 100 ma.
2.4 Gas Flow Limits
The GTFM can be used to test for High/Low gas flow limits. An internal fault relay
will be set (CLOSED) when the gas flow is within the programmed limits. The fault
relay can be interfaced to an external weld fixture controller.
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