How to Wire a Temperature Switch (Thermostat)‌

Here's the professional English translation of the temperature switch wiring guide:

How to Wire a Temperature Switch (Thermostat)‌

The wiring of a temperature switch (thermostat) depends on its type and function. Below are universal wiring methods and key considerations:

I. Power Supply Wiring‌

Confirm Supply Voltage‌

Most thermostats operate on ‌220V AC‌. Connect power wires to terminals marked "AC 220V," "Power," "L/N," or equivalent (typically terminals 8-9, 2-3, or L/N) ¹²³⁴⁶.

Wiring Standards‌

Line (L) and Neutral (N) wires don’t require strict polarity but must be securely fastened ⁵.

For high-power devices (>1000W), use a ‌contactor‌ for control—the thermostat only provides a control signal ⁴⁵.

II. Output Control Wiring‌

1. Relay Output Type‌

Controlling Heating Devices‌:

Connect ‌Normally Open (NO) contacts‌ (e.g., terminals 7-8, 12-13) in series with the contactor coil circuit ³⁴⁶.

Contacts ‌close‌ to start heating when temperature falls below the setpoint; ‌open‌ when temperature is reached ²³.

Alarm Function‌:

Alarm terminals (e.g., 10-11, 4-5) are typically ‌NO contacts‌ that ‌close‌ during overtemperature to activate alarms ³⁴.

2. Solid-State Relay (SSR) Control Type‌

Output terminals‌ (e.g., 12-13) require polarity:

Terminal 12 → SSR positive (+)

Terminal 13 → SSR negative (–) ²³.

The thermostat outputs a ‌DC voltage signal‌ to drive the SSR ³.

For direct control of low-power devices, connect the output in series with the load and power supply ⁵.

III. Temperature Sensor Wiring‌

Thermocouple/RTD Sensors‌

Connect 2-wire sensors according to polarity to designated terminals (e.g., 9-10: Terminal 10 → red wire/positive; Terminal 9 → blue wire/negative) ¹².

Terminals are labeled "Temp," "Sensor," or equivalent—ensure secure connections to avoid measurement errors ¹².

IV. Wiring Precautions‌

Power Off‌: Always disconnect power before wiring ⁵.

Power Matching‌:

Relay outputs typically support ≤10A load current. Exceeding this requires an external contactor ⁵⁶.

SSR control must match the drive voltage ³.

Functional Verification‌:

After power-up, set temperature values and test whether output contacts activate correctly during heating/cooling ¹².

💎 Critical Note‌: Terminal definitions vary significantly by model. Always consult the device manual or on-body wiring diagram before proceeding ³⁴⁶.

Key Terminology‌:

常开触点 (cháng kāi chù diǎn) → Normally Open (NO) contacts

接触器 (jiēchù qì) → Contactor

固态继电器 (gùtài jìdiànqì) → Solid State Relay (SSR)

复位 (fùwèi) → Reset

火线/零线 (huǒ xiàn/líng xiàn) → Line (L)/Neutral (N)