Martel Electronics 135 - Manual (Page 36)

Pressure Module (Optional)
The Pressure Module allows a Model 130/135 calibrator to make the
precise pressure measurements required for calibrating field pressure
instruments. The Pressure Module is a measurement only device. The
source of pressure must be supplied externally, usually by a hand
pump.
Electrical Connections
The Module attaches to the calibrator’s feature connector, located at
the bottom of the unit. The connector is keyed to prevent improper
installation.
Pressure Connections
The Pressure Module has a female 1/8 inch pipe thread for making the
pressure connection. The fitting is 316 stainless steel. A suitable
thread lubricant should be used when making the connection to
prevent seizing or galling.
Media Compatibility
The Pressure Module is designed to provide optimum accuracy as a
secondary calibration device. It is not designed to be a general purpose
test gauge to be attached to live processes. The low pressure ranges
(0-100 PSIG) are compatible with non-corrosive gases. For long service
with good stability and accuracy, clean, dry instrument air or nitrogen
should be used. The high pressure ranges (300-5000 PSIG) are
compatible with non-corrosive liquids and gases. The best liquid to use
is distilled water.
Operation
The Pressure Module is activated by pressing the OPT key just as you
would with any of the other function keys, such as volts or milliamps.
Input Functions
130/135 32
The pressure module should only be connected while the calibrator
is off.