Michell Instruments Easidew Online, Руководство пользователя

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Easidew Online User’s Manual
26 97094 Issue 18.5, March 2016
OPERATION
3.2 Preparation For Operation
3.2.1 First Time Operation
To commence operation, proceed as follows:
1. Check that electrical power supply and the relevant analog and alarm
outputs are connected to external systems as required and as described
in Sections 2.8 and 2.13.
2. Check that the gas sample fl ow rate through the sample block, or the
pipeline in which the transmitter is located, is within the operational
limits. (Adjust any external fl ow control valves, located in the gas sample
input line to the instrument to achieve required fl ow rate.)
3. Switch on the power supply to the instrument. The instrument display
will now come on, typically showing the default parameters and units as
detailed in Figure 23.
The instrument is now operational and after a few seconds, in which all the segments
of the display are tested, the monitor will display the measured dew-point temperature
as a steady reading within the range -100 to +20°Cdp (-148 to +68°Fdp) or 0 to
3000 ppm
V
depending upon how the instrument has been set-up. The default setting is
degrees Celsius.
In the absence of any error indications the instrument will now be operational using the
default parameters.
Easidew Online Hygrometer
Figure 23 Typical Display
If the display is fl ashing, a fault condition exists. The following operational error
conditions may be encountered:
ErrL
- If the display is alternately fl ashing (e.g.)
ErrL
and
-103.3
, this
indicates that the measured dew point is outside the lower operational limit
(-100°Cdp/-148°Fdp).
If the display is alternately fl ashing
ErrL
and
-129.9
(
-199.9
if set-up to read
temperature in °F), this could be an indication that the input current loop to
the monitor is open or that there may be a transmitter fault. Check that the
transmitter is wired correctly as detailed in Sections 2.10 and 2.12.
ErrH -
If the display is alternately fl ashing (e.g.)
ErrH
and
021.4
, this
indicates that the measured dew point is outside the upper operational
limit (+20°Cdp/+68°Fdp).