Heatcraft Refrigeration Products 25001501 - Manual (Page 5)

BEACON CONTROLLER
5
REFRIGERANT LINE BRAZING (CAUTION)
The electric expansion valve on the liquid line and the suction temperature sensor on the suction line are
factory installed. Care must be taken when brazing these lines at the evaporator.
Too high a temperature
may destroy these components. Heat absorbing compounds or “wet rags” must be used when braz-
ing the refrigerant line connections and the suction line sensor removed per above instructions.
WIRING
Wiring between the condensing unit and unit cooler(s) will be as follows (see attached wiring diagrams):
• High voltage - To the defrost heaters (if present) and/or fan motors. See unit cooler spec plate for ampacity.
The evaporator may also be connected to a separate power supply.
• Low voltage - 24V (18 to 30) VAC Class II control circuit. A total of 5 low voltage leads are required to
connect the condensing unit to the evaporator. Two of these leads are for connecting the compressor
discharge sensor. The other 3 leads are for connecting the compressor relay and the 24V transformer. All
24 volt wiring must be separated from the line voltage wiring.
• Compressor discharge line sensor - Use 18 gauge wire. Must be run separate from other high voltage
power wiring.
• Smart Controller (Optional) - Use 18 gauge wire. For extra long runs, 16 gauge wire may be required. Low
voltage wiring must be run separate from other high voltage power wiring.
• Slave unit(s) (if used) - Connect the multi-out terminal on the master unit to the multi-in terminal on slave
unit and the 24V (18 to 30) VAC from the master unit to the slave unit. (See wiring diagram.)
• Alarm circuit - The onboard alarm is a dry set of NC contacts which closes to indicate an alarm. Type and
wiring for the alarm is customer specified. Note that the alarm circuit does not distinguish or indicate what
has caused the alarm. (See “ALARMS”.)
Note: All wiring must comply with all applicable codes and ordinances.
ROOM TEMPERATURE CONTROL
Three methods are available:
• Each Beacon board is shipped with a fixed resistor (attached) that controls the room temperature set-
point. Air defrost boards are set for 35˚F with a 15K ohms resistor. Electric defrost boards are set for -10˚F
with a 100K ohms resistor.
• In the packet are additional resistors which can be used for other room temperature set-points. These
resistors are color coded. The table below shows the settings.
Resistor Color Resistor Value Set-point
Tape Ohms Temperature
Black 100K -10˚F
Green 70K 0˚F
White 30K 20˚F
Blue 20K 30˚F
Yellow 15K 35˚F
Red 10K 40˚F
• To change the room set-point, remove the resistor attached to the Beacon board and attach the resistor
value required for your set-point temperature. If you need a value not shipped in the packet, you may
purchase a 1/8W to 1/2W resistor from an electronics store (i.e. RadioShack), for the ohm values shown.
• These resistors will control the room temperature at the approximate temperatures shown. These values
are also to be used for setting the Beacon board thermostat pot.