H-Tronic TDR 2004 PRO Temperature Difference Controller, -99 to +850 °C 1114770

Heating and solar engineers use the H-Tronic TDR 2004 PRO to manage temperature differences in thermal systems. Mounted on a DIN rail in a control cabinet, it compares two PT1000 sensors and switches a 16 A relay when the measured difference exceeds the set threshold.

Key specifications

• Operating voltage: 230 V/AC, 50/60 Hz
• Measurement range: -99 to +850 °C
• Sensor inputs: 2 × PT1000 (2-wire)
• Relay output: 1 potential-free changeover contact, 16 A / 230 V/AC (ohmic load)
• Display: 3-digit LED, resolution 0.1 °C up to 99.9 °C, 1 °C above 100 °C
• Control modes: differential (heating/cooling), absolute (min/max)
• Adjustable differential: 0.1 to 99.9 °C
• Adjustable hysteresis: 0.1 to 99.9 °C
• Functions: frost protection, overheating protection, pump control, solar control
• Mounting: DIN rail TS35
• Power consumption: approx. 2 VA
• Ambient operating temperature: 0 to +50 °C
• Protection class: IP20
• Electrical connections: screw terminals
• Sensor error detection: yes

Why choose it

The TDR 2004 PRO combines a wide temperature range with precise differential control. Its potential-free relay can switch loads up to 16 A directly, and the LED display shows measured values and settings clearly. Frost and overheating protection functions add safety for pumps and collectors.

Ideal use cases

• Solar thermal systems: control circulation pump based on collector-storage temperature difference
• Heating systems: manage boiler or storage charging
• Industrial processes: monitor and control temperature differences in tanks or lines

Good to know

The controller is designed for DIN rail mounting in electrical enclosures. It requires two PT1000 sensors (not included) and a 230 V/AC supply. The screw terminals accept standard wiring.