User Manual

CM1N1514E
2020-12-21
Smart Infrastructure
s
1
514
Duct Hygrostats QFM81…
for relative humidity
QFM81.21
QFM81.2
On/off hygrostat with microswitch,
with temperature-compensated humidity sensor for temperature-independent
humidity measurements,
with stabilized sensing strip (good linearity, very stable even at high humidity,
insensitive to dust and contaminated air),
for the control of humidification equipment,
for the control of dehumidification equipment,
for mounting in ventilating ducts or rooms
The duct hygrostats are designed for controlling and monitoring the relative humidity in
ventilating and air conditioning plants.
They control the humidity content of the air within an adjustable range of 15 to 95 % r.h.
In air conditioning plants with humidification, the duct hygrostat can also be used as a
maximum limiter in the supply air duct.
In laboratories or production facilities, the duct hygrostat can also be used as a mini-
mum limiter in the supply air duct.
Type Order number
Setpoint
range (W
h
)
Switching
differential
(X
d
)
Degree
of pro-
tection
Setpoint
adjust-
ment
QFM81.2 BPZ:QFM81.2
15…95 %
r.h.
approx. 4 %
r.h.
IP30 externally
QFM81.21 BPZ:QFM81.21
15…95 %
r.h.
approx. 4 %
r.h.
IP55 internally
When ordering, please give name and type reference; for example:
duct hygrostat QFM81.2
The delivery comprises the hygrostat, a mounting flange (for duct or wall mounting) and
a sealing ring (for duct mounting).
Use
Type summary
Ordering and
deli
v
ery