EX-5100 C
OMBUSTIBLE
ENMET
9
5.2 Calibration of the EX-5100
Calibration is the process of setting the instrument up to read accurately when exposed to a target gas. The Zero function sets
the clean air reference point and the Span function sets the sensitivity of the instrument.
Initial Calibration:
Wait 24 hours after initially supplying power to the
EX
-
5100
sensor/transmitter (S/T) before initial calibration. The S/T has
been precalibrated at the factory, and initial field calibration should result in only fine tuning to circuit, as well as a way to
check that installation is successful. It is not necessary to open the enclosure to make adjustment; the span and zero
potentiometers are operated with magnets from outside the enclosure. Do Not open the S/T unless the area is de-classified.
Calibration Zero and Span functions are two separate procedures. They operate independently of each other. It is
recommended that the Zero procedure be done prior to the Span procedure.
ENMET
recommends at least quarterly calibration
of the
EX-5100
transmitters.
Calibration equipment is available from
ENMET
to calibrate the
EX
-
5100
sensor/transmitter. A calibration adapter will have a
fitting for the gas cylinder on one side and a cover to go over the sensor housing on the other.
Generally, a cylinder of 20.9% Oxygen is used to provide a fresh air reference or Zero point for the calibration. Another
cylinder is used to provide the Span reference point for calibration. Depending on the instrument calibration, the Span gas may
be the same gas that the instrument is calibrated to display, or it may be another gas, which
ENMET
has found to have a similar
response.
Figure 4: Calibration Adapter EX-5100 Sensor/Transmitter
S
e
le
c
t
M
e
n
u
Select
Menu
Fitting to
calibration cover
Regulator
Gas Cylinder
Calibration Cover
p/n 03620-015
