RKI Instruments RI-215A - Manual (Page 16)

16 • Overview RI-215A Operator’s Manual
Chapter 4: Operation
Overview
This chapter describes Measuring Mode and Alarm Adjust Mode. Under Measuring
Mode, alarm indications are discussed along with responding to alarms, analog output,
and alarm point and ventilation control. Under Alarm Adjust Mode, verifying the alarm
point and adjusting the alarm point are described.
Measuring Mode
When the RI-215A is in Measuring Mode (normal operation), it displays the current
concentration of CO
2
on its LCD and outputs a 4 - 20 mA signal that corresponds to the
CO
2
concentration. The typical background CO
2
level is 200 - 400 ppm.
Alarm Indications
If the CO
2
concentration rises above the alarm point, the relay contact will actuate. If the
gas concentration exceeds the full scale, the LCD shows:
Responding to Alarms
1. Follow your established procedure for handling high levels of CO
2
gas.
2. When the display reading falls below the alarm point, the alarm circuit automatically
resets itself.