Danfoss TT400 Series User Manual

Page 29 of 108
M-AP-001-EN Rev. N
Control Interface Wiring
Table 4-1 - Control Wiring
Details
To ensure proper control wiring techniques, follow these guidelines:
1. The ground reference of the external circuit connected to the Compressor I/O Board
must be at the same potential as the ground reference on the Compressor I/O Board.
2. The Interlock circuit should be voltage-free. For instance, all external contractors/
switches must not introduce current into the circuit.
3. Analog outputs (such as Motor Speed) must be received by the external circuit without
sending current back to the Compressor I/O Board.
4. All interlock and analog output cables should be shielded with one end of the shield
connected to the common analog or digital ground bus. The other end of the shield
must not be grounded as this would create a ground loop. Refer to Figure 4-2.
4.1 Control Wiring
Connection Guidelines
I/O Description
COM (shield) Shield for RS-485 communication
Modbus RS-485 NetB/NetA Modbus over RS-485 communication port
Stepper Motor 1 Phase 1A, 1B, 2A,
2B and
Stepper Motor Phase 1A, 1B, 2A,
2B
Optional output connections for controlling the main electronic expansion
valve (evaporator) or auxillary electronic expansion valve (economizer or load
balancing valve). 200ma Maximum output on each driver. Valve frequency
will eect operational characteristics.
Level Sensor +15V (Evaporator) Power supply for level sensor #1
Sensor Signal (Evaporator) Input from a level sensor to control the main expansion valve (evaporator)
Level Sensor +15V (Economizer) Power supply for level sensor #2
Sensor Signal (Economizer)
Input from a level sensor to control the auxiliary expansion valve
(economizer)
Demand 0 - 10V
Analog input from customer-supplied controller to drive the compressor, i.e.,
0 - max. kW input with a deadband of 2VDC for the respective compressor
model. Only available in 3.1.4; removed in 4.x forward.
Interlock
Connects to a set of external normally closed contacts that typically open in
the event of loss of chilled water or air ow. Typically a 1.5VDC Output signal.
NOTE: This is not a safety certied interlock.
Status
An internal normally open contact that is closed during normal operation
and opens in the event of a compressor fault. With the circuit open, the
compressor will not restart until the demand signal has been reset to 0 (via
chiller/unit controller). Circuit rated at 1A @ 30VDC/24VAC or .03A @ 120VAC.
Liquid Temperature
Optional input for monitoring temperature. The temperature sensor must be
an NTC type 10K @ 25°C thermistor.
Run
An internal N/O contact that is closed while the compressor is running.
The speed at which the contact closes is user-congurable via the monitor
program. Circuit rated at 1A @ 30VDC/24VAC or 0.3A @ 120VAC.
Analog
Universal analog output manually controlled as a percentage of total voltage
written through Modbus. This can be congured for 0-5V or 0-10V via on
board jumpers.
Entering Chilled Water Temp
Analog input indicating water temperature. The temperature sensor must
be an NTC type 10K @ 25°C thermistor. Refer to Application Manual for
thermistor specication.
Leaving Chilled Water Temp
Analog input indicating water temperature. The temperature sensor must
be an NTC type 10K @ 25°C thermistor. Refer to Application Manual for
thermistor specication.
Spare T +/-
Optional input for monitoring temperature. The temperature sensor must be
an NTC type 10K @ 25°C thermistor.
Spare P +/- Can be connected to a 0-5V type pressure sensor

Danfoss TT400 Series Specifications

General

Brand	Danfoss
Model	TT400 Series
Category	Compressor
Language	English