Pressure module (optional) – Martel Electronics 235 User Manual
Page 41

calibrator will prompt for the type of connection: 2-wire, 3-wire, or 4-
wire.
Select the type of connection you will be using and press ENT. For
actual calibration, the more accurate 3-wire or 4-wire method should
be used. The calibrator will begin making RTD measurements and
display the readings on the left-hand side of the display.
The top line of the display contains information about the
measurements being made. The first three characters indicate that
RTD is selected.
Next is the termination method selected and then the temperature
scale.
Pressure Module (Optional)
The Pressure Module allows a Model 230/235 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
Input Functions
230/235
36
The pressure module should only be connected while the calibrator
is off.
Termination type
2W 3W 4W
RTD 4w°F
+ 212.0