Vaisala HMP230 User Manual
Page 26
HMP230 SERIES
User's Guide
M210225en-B
20
Figure 19 Installing the sensor head for by-pass measurements.
When pushing the probe head through the ball valve assembly, be careful not
to break the sintered filter. Open and close the ball valve assembly with the
marking groove always in sight. In by-pass measurements, the clasp nut is
tightened manually prior to pressing the probe through the valve. When the
probe has been pressed through and the valve is open, the nut is tightened
50...60
°
with a fork spanner (hexagon 27 mm).
3.3.
Grounding
A single electrical cable with a screen and three to ten wires is recommended
for power and analogue output/serial bus connections. The cable diameter
should be 7...10 mm.
The screen of the electrical cable must be grounded properly to achieve best
possible EMC performance. Recommended cable shield is done in the cable
gland as shown below.
•
remove the brass disks, rubber ring and nut from the transmitter
housing
•
strip 165 mm of the cable insulation, but leave 25 mm of the braid
visible
•
slip the nut and rubber ring over the cable insulation