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© 2022 All rights reserved. Data subject to change without notice.
FCS - Operation Manual
Rev. C | 2022.02
Use the + or - buttons or press the yellow fields and use the keypad to change the values, for
each analog output. You can select:
A. Output:
Select the analog output number of the analog output you are calibrating.
Output (mA):
Enter the desired output value (ie. 4 mA or 20 mA).
D/A @ 4 mA:
When requesting 4 mA output, change the number until the amp meter
reads 4 mA.
D/A @ 20 mA:
When requesting 20 mA output, change the number until the amp meter
reads 20 mA.
Press SAVE to save the changes.
NOTE:
Each AO channel number must be calibrated for a low and a high range (ie. 4 mA and
20 mA). Because the D/A counts can fluctuate in relation to each other, when finished, double
check to ensure both values have remained acceptable. Adjust if required.
NOTE:
CETCI uses 4 mA and 20 mA defaults, if other mA values are desired, follow the same
steps using the preferred mA value instead of 4 mA and 20 mA.
10 STEL AND TWA SETTINGS
STEL (Short-term Exposure Limit)
The STEL is the acceptable average exposure over a short period of time, usually 15 minutes
as long as the time-weighted average is not exceeded at any time or so many times in
succession (depends on local regulations) during a workday. The concentrations are given in
ppm. For example, the STEL for CO is 100 ppm.
TWA (Time Weighted Average)
The TWA indicates a time-weighted average concentration for up to an 8 hour (OSHA) or a
10 hour (NIOSH) workday during a 40 hour week. The concentrations are given in ppm. For
example, the TWA for CO is 25 ppm.
IDLH (Immediately Dangerous to Life and Health)
IDLH is defined by NIOSH and OSHA as exposure to airborne contaminants that is “likely to
cause death or immediate or delayed permanent adverse health effects or prevent escape
from such an environment”.
NOTE:
IDLH level for a particular gas may be above the measurement range. For example,
the measurement range for CO is 0 to 200 ppm. The IDLH is 1,000ppm.