Analog/Digital Inputs; Read Analog Inputs; Setup Analog Inputs; Read Digital Inputs - Liebert Himod Operation & Maintenance Manual

3.11

Analog/Digital Inputs

Selecting ANALOG/DIGITAL INPUTS steps to the following menu:

• READ ANALOG INPUTS

• SETUP ANALOG INPUTS

• READ DIGITAL INPUTS

• SETUP DIGITAL INPUTS

3.11.1 Read Analog Inputs
The four (4) analog sensor inputs can be monitored from the display. The inputs are filtered, then dis-
played along with the text label assigned during setup.
3.11.2 Setup Analog Inputs
For installation of analog sensors, see Analog Setup on page 11
After selecting a compatible sensor and properly wiring it to the terminals, set up the control to mon-
itor the sensor as follows:
Slope
The slope is a multiplier used to scale the input signal. The slope can be positive (rising) or negative
(falling) and can range from 0 (resulting in a horizontal line) to ±999. The slope for a 0-5 volt input is
per 1 volt input, for 0-10 volt input is per 2 volt input, and for 4-20 mA is per 4 mA input. For exam-
ple, assuming an intercept of 0, for a 0-10 volt sensor input with a slope of 50, an input of 1 volt would
be displayed as 25: (1x[50/2]), 2 volts would be 50: (2x[50/2]), 3 volts would be
75: (3x[50/2]), etc.
Intercept
The intercept is an offset from point 0 corresponding to 0 volts or 0 mA input. The intercept can be
positive or negative and can be a point from 0 to ±999. Adding an intercept of 100 to the slope example
above, 1 volt would be 125: 100 + (1x[50/2]); 2 volts would be 150: 100 + (2x[50/2]); 3 volts would be
175: 100 + (3x[50/2]); etc.
NOTE
For a 4-20 mA input sensor, if the desired reading at 4 mA input is 0, then an intercept of
-1 x slope would be required. For example, assuming a slope of 50, the formula would be
([-1 x 50] + 4 x [50/4]) = 0. The intercept is -50.
Text
You may enter a custom label for each analog input. The text label can be 20 characters in length
including any of the following: ABCDEFGHIJKLMNOPQRSTUVWXYZ#%*-0123456789, or space.
3.11.3 Read Digital Inputs
The four custom alarm inputs can be defined to be digital inputs. Digital inputs are used to sense cus-
tomer devices for status display purposes only and will not activate the audible alarm.
3.11.4 Setup Digital Inputs
A digital input is enabled by defining one of the four custom alarms to be STATUS ONLY type in the
alarm setup screen. The digital input is given a name by specifying it to be one of the optional alarms
or a custom text alarm. See 3.4.3 - Setup Alarms and 3.4.4 - Setup Custom Alarms.
Operation with Advanced Microprocessor with Graphics Control 25