Distech Controls HS-THX Installation Manual page 3

Make wiring connections as per the "Wiring" illustrations. Once the wiring and device setup are complete, re-install the cover and secure with the four
screws as shown in Figure 5.
Figure 5: Closing the enclosure.
Wiring
Deactivate the 24 Vac/dc power supply until all connections are made to the device to prevent electrical shock or equipment damage. Follow proper
electrostatic discharge (ESD) handling procedures when installing the device or equipment damage may occur. Use 14-22 AWG shielded wire for all
connections and do not locate the device wires in the same conduit with wiring used to supply inductive loads
such as motors. Pull at least six inches of wire into the enclosure and complete the wiring connection according to the wiring diagram. Make all connections
in accordance with national and local codes.
Connect the plus DC or the AC voltage hot side to the POWER terminal and the power supply common is connected to the COMMON terminal. The
device is reverse voltage protected and will not operate if connected backwards. It has a half-wave power supply so the supply common is the same as
the signal common. Use caution when wiring multiple devices or when grounding the secondary of a transformer to ensure that the circuit ground point
is the same on all devices and the controller.
The analog outputs are available on the TEMP and RH terminals. The signal type may be ordered as either voltage or 4-20 mA active outputs. The
voltage model is selectable for either 0-5 or 0-10 Vdc via the menu (the factory default is 0-5 Vdc). The current outputs operate in the active mode and do
not require a loop power supply. This means that the signal current is generated by the horticulture sensor and the outputs must not be connected to a
powered input or device damage will result. Check the controller Analog Inputs (AI) to determine proper connection before applying power. Both current
and voltage output signals are referenced to the COMMON terminal. The analog output signals are typically connected directly to the Building Automation
System (BAS) and used as control parameters.
The horticulture sensor may have one or two optional relays installed. The relays are Form C type with both a normally open (NO) and a normally closed
(NC) contact. The relay contacts may be connected to controller Digital Inputs (DI) for status monitoring or used to directly control an alarm or ventilation
fan. Do not exceed the device contact ratings. In some cases a separate control relay may be used between the horticulture sensor relay and a large fan
for example.
Relay terminals are designated NO, COM and NC. Each relay output is independent and isolated from the other and the relays COMs are not connected
to the device COMMON.
Typical wiring diagrams are shown in Figure 6.
Figure 6: Wire Termination for Thermistor.
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