Electrical connections – Vaisala HMT360 User Manual
Page 37
Chapter 3 _______________________________________________________________ Installation
VAISALA_______________________________________________________________________ 35
Electrical Connections
Refer to local requirements regarding cabling, grounding and galvanic
isolator or barrier connections.
1.
Open the transmitter cover and remove the protective cover of the
transmitter base.
2.
Thread the power supply wires through the cable gland, see
.
3.
Connect the unpowered power supply wires to the connectors: Ch 1
(humidity) and Ch 2 (temperature). Both channels require an own
power supply.
4.
Replace the protective cover. Turn the transmitter on ON with the
ON/OFF switch, see
5.
Close the cover. The transmitter is ready for use.
When using the transmitter in hazardous locations, the use of galvanic
isolators or barriers is essential. The following barrier & isolator are
available in Vaisala: barrier No. 210664 (STAHL 9001/51-280-091-141)
and galvanic isolator No. 212483 (STAHL 9160/13-11-11). Examples of
connections and more information on installation in hazardous locations is
given in section
Examples of Connections on page 41
WARNING
Connect the transmitter always via galvanic isolators or Zener barriers in
hazardous environments.
WARNING
Be sure that the main power switch of the transmitter is set off before
making any electrical installations in hazardous areas.
NOTE
As Ch 1 is a main output, the transmitter does not operate if only Ch 2 is
connected (Ch 2 is optoisolated from transmitter electronics).