Martel Electronics 135 - Manual (Page 14)

If the module is not capable of operating in the mode requested, an
error message will be displayed.
The operation of the Pressure Module can be found on page 31.
Ramp Key
The RAMP key is used to activate the ramp function which is covered in
the next section under Output Functions.
% Key (Model 135 Only)
The % Key allows easy access to the % Error Function. If the % ERR
Function has been set up using the SETUP menus (see page 19), press
the % Key to alternate between the Engineering Unit display and the %
ERR display.
SYS Key (Model 135 Only)
The SYS Key allows the Model 135 Calibrator to be used with a
Calibration System Database. Refer to the Calibration System Database
Instruction Manual for system information. Operation of the calibrator
is covered in this manual.
To enter the System mode of operation, press the SYS Key. The display
will show the tag number of an instrument previously loaded into its
memory on the top two lines of the display. Additionally, its sequence
in the group previously loaded from 01 to 28, and whether or not it has
been calibrated, is also indicated.
Operation
130/135 10
MCC #2 ET-101-
34688-A1-B
SEQ=01 READY