Belimo CR24 Series, Product Information

Page: 22 / 32

Functions
CR24-..
22 www.belimo.com
Pr
oduct information S4-CR24-.. • en • v2.3 • 08.2022 • Subject t
o changes
ao1 ao3
Y [V]
t
R
[°C]
W
A
ao2
10
2
0
1 2
12
~ +
di3
AC 24 V
CR24-B3
ao1 ao3
Y [V]
t
R
[°C]
W
A
ao2
10
2
0
1 2
12
~
+
di3
AC 24 V
CR24-B3
The CR24-B3 resp. CR24-B2E controller allows override control at
the digital input di3, to enable the room to be heated or cooled with the
maximum capacity. This function acts on all three analog outputs (see
"Notes").
Typical applications
– Rapid heating, rapid cooling
– Cooling, morning boost etc.
Notes
The boost function acts temperature-sensitive on the outputs as follows
CR24-B3:
– ao1 (VAV) 100% > 10 V (V′
max
)
– ao2 (heating/cooling) 100% > 10 V
– ao3 (heating) 100% > open (3-point)
CR24-B2E:
– ao1 (VAV) 100% > 10 V (V′
max
)
– do3 / 1 ON
– do3 / 2 ON
To support reheater applications the VAV system output (ao1) gets
activated at the heating condition too.
The boost function is deactivated by the following events:
– Boost signal (di3) not active
– Comfort setpoint (W) reached
The air is always conditioned to the comfort setpoint W, even if stand-by
(d1) is active, in order to facilitate room preconditioning.
Boost – V'
max
Digital input di3 CR24-B3 only
Configuration
This boost function is configured using DIP
switches 4 (boost on) and 5 (boost V′
max
).
2 3 4 5 6 1
Configuration (CR24-B3 only)
This boost function is configured using DIP
switches 4 (boost on) and 5 (boost temperature-
controlled).
2 3 4 5 6 1
Boost – V'
max
Boost
Boost – Temperature-controlled
Boost
Auto
Boost
Auto
Boost
The CR24-B3 controller allows override control at the digital input di3,
to enable the room to be ventilated with the maximum air flow (V′
max
).
This function acts on all three analog outputs (see "Notes"). Room tem -
perature control is deactivated in this mode (exception: frost protection
function).
Typical applications
– Purging conference rooms, hotel rooms etc.
– Assisting smoke extraction
– Free- or night cooling
Notes
The boost function acts on the outputs as follows:
– ao1 (VAV) 100% > 10 V (V′
max
)
– ao2 (heating/cooling) 0% > 0 V
– ao3 (heating) 0% > closed (3-point)
The boost function is deactivated by the following events:
– Boost signal (di3) not active
– Frost limit temperature (10°C) undershot
Boost – Temperature-controlled Digital input di3 CR24-B3, CR24-B2E
Key
Y
Output signal
t
R
Room temperature
W
A
Current setpoint
Key
Y
Output signal
t
R
Room temperature
W
A
Current setpoint