Location Of Sensors (2 Circuits) - Carrier 50EN 415 Installation, Operation And Maintenance Instructions

8 - ELECTRICAL CONNECTION

8.6 Location of sensors (2 circuits)

B2
Outdoor temperature probe
Outdoor fan
B3
Supply
air probe
Outdoor coil
B7
Press. transducer
in the outdoor
coil cir. 1
Indoor fan
Indoor coil
CIRCUIT 1
B4
Mixing
probe
Reversing
valve
(heat pump)
Discharge T
klixon switch
B1
Return air probe
B5
Compressor Ambient air probe
High pressure Low pressure
B10
Air quality
probe (opt.)
Note: If the unit needs the outdoor humidity probe (used with
enthalpic or thermoenthalpic free-cooling), this one will be
connected in B5 in the place of the NTC ambient probe. In this
case it is necessary to use a RS485 ambient temperature probe
connected on the Field-bus.
The outlet probe (B3) and the mixing probe (B4) can be replaced
by RS485 enthalpic probes for calculation of the cooling and
heating capacities (optional).
8.7 Sensors connection by the costumer
The client must connect on-site the following probes:
● Ambient NTC (standard) or RS485 (optional).
● Air quality (optional).
● Outdoor humidity (optional).
These probes are supplied inside the main electric panel of the
50EN/EH unit.
Please refer to the wiring diagram and the CARRIERrtc
control brochure, both provided with the unit.
Connection of the ambient probe
● Open the case using a fl athead screwdriver in the slot, paying
extra care not to damage the electronic parts.
Outdoor fan
Outdoor coil
B12
Press. transducer
in the outdoor
coil cir. 2
Indoor coil
Fresh
air
CIRCUIT 2
Reversing
valve
(heat pump)
Extraction
Discharge T
klixon switch
Compressor
Low pressure High pressure
● Fasten the rear of the sensor case to the panel or the wall (for
fastening the case, use the screws supplied with the fastening
kit, paying attention to use the proper spacers, to not damage
the sensor's electronics).
● This probe must be fastened to the panel or the wall of the
room to be conditioned, at ca. 1.5 m height.
● Close the sensor with the top cover by pressing lightly.
Electrical connection
● Make the electrical connection according to the unit
confi guration:
- NTC probe (B5 - connector J3) : with 2 x 1,5 mm
cable, within a maximum distance of 30 meters.
- 1 to 4 RS485 probes of temperature or temperature+
humidity (connector J10): with AWG20 section cable, single
braided pair preferably shielded with drain wire + Power
supply 24 Vac (2 wires).
Note: in the case of more than one probe, connection of the
probes in series, in the RS485 network. Please, refer to the
CARRIERrtc control manual.
Connection of the outdoor humidity probe (optional)
The outdoor humidity probe (optional on B5 - connector J3),
necessary for the enthalpic and thermo-enthalpic free-cooling,
must be installed on-site, on the hood of the fresh air intake.
● Open the case by turning the top cover anticlockwise (fi g1).
● Fasten the rear of the sensor case to the side panel of the
hood (use the screws supplied together with the probe) placing
the screws in the holes provided (fi g.2).
● Make sure that the screws that hold the board protective cover
are fastened tightly (fi g.3).
● Close the sensor by turning the cover clockwise (fi g.4).
(fi g.1)
(fi g.3)
2 section
(fi g.2)
(fi g.4)
15