EB 9520 EN
19
Operation
2. Close the equalizing valve or bypass of
the valve block.
3. Open the low-pressure line.
4. Check zero (see section 6.1) and put the
device back into operation.
−
During measurement, make sure that the
equalizing valve is closed and the shut-off
valves are open.
−
In cryogenic applications, the process me-
dium circulates during measurement when
the equalizing valve is opened, causing the
valve block to ice up.
6
Operation
6.1
Checking zero
Zero can also be checked while the system is
running, provided the differential pressure
lines are equipped with shut-off and equaliz-
ing valves.
1. Close the shut-off valve in the high-pres-
sure line.
2. Open the equalizing valve.
3. Close the shut-off valve in the low-pres-
sure line to allow the pressures to equal-
ize in the dp cell.
Î
The pointer must indicate zero.
If this is not the case, undo the dial
screws and turn the dial (it can be turned
by 4° at the maximum).
NOTICE
!
In case of larger deviations, remove the
pointer with an appropriate tool. Align
the dial plate in the mid-position. Re-
mount the pointer on the axis in the zero
position.
To start-up:
1. Open the low-pressure line.
2. Close the equalizing valve.
3. Slowly but gradually open the high-pres-
sure line all the way.
4. The device is in operation again.
Î
If a valve block is installed, proceed as
described above.
Dial screws
Fig. 6:
Zero point calibration (turning the dial)
6.2
Water drainage
When measuring gas, drain condensed wa-
ter from the separation chambers from time
to time. Close valves in the differential pres-
sure lines (valve block) before opening the
drain plugs.
