RKI Instruments M2 for 12 VDC - Manual (Page 18)

13 M2 Transmitter Operator’s Manual, 12 V DC Operation
Chapter 4: Operation
Overview
This chapter describes the M2 in normal operation. This chapter also describes the M2 in
alarm 1, alarm 2, and fail conditions and suggests response to these conditions.
Normal Operation
Normal operation is defined as follows:
• The start-up procedure is complete.
• The M2 is not indicating an alarm 1, alarm 2, or fail condition.
• The M2 is not in Calibration, Configuration, or Gas Type modes.
During normal operation, the M2 simultaneously displays the current gas reading, unit of
measure, and target gas. The example below illustrates a typical LEL M2.
Information Screen
The Information Screen displays the M2’s operating voltage and firmware and hardware
information. To display the Information Screen, do the following:
1. Press and hold the DOWN/NO button for 3 seconds. The Information Screen will
appear.
2. Continue holding the DOWN/NO button to keep the Information Screen on the
display. The top line indicates the operating voltage that is connected to the M2. The
second line indicates the firmware that is running, version 5.0 in this example, and the
M2’s hardware version, version 1B in this example. This information may be useful if
you need to contact the factory with questions about the M2.
3. Release the DOWN/NO button when you are done viewing the Information Screen.
The display will return to the normal operation screen within a couple of seconds.
4 - 20 mA Signal Output Operation
The output at the S terminal of the power/signal terminal strip is a 4 - 20 mA signal that is
proportional to the detection range of the detector head. During normal operation, this
signal tracks the gas concentration on the LCD.
There are several circumstances where the signal output will not track the display reading
but will behave as follows:
METHANE
0 %LEL
12.1V
v5.0L 1B