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CROUZET CONTROL

CROUZET CONTROL

Temperature monitoring relays HT81, HWT81 - OBSOLETE

  • OBSOLETE WITH NO REPLACEMENT
  • Temperature monitoring, lift machinery room per EN81
  • Adjustable control between +4°C and +40°C
  • PT100 input
  • Phase monitoring

Product description

Control relay for temperature monitoring in lift machinery rooms, used for monitoring of temperatures between +4 °C and +40 °C per the EN 81 standard.

HT81 : As long as the temperature that is controlled by the PT100 sensor is between the two limit values, which are preset at the front, the relay output is activated and the yellow LEDs are on.

When the temperatures is over or under one of these limit values (upper or lower), the time delay (Tt), which is set at the front, begins to count down. The yellow LED for the set limit value (upper or lower) flashes. If the temperature is still too high or low after the time delay, the relay drops out and the yellow LED turns off. As soon as the temperature returns to the set range, the relay activates (allowing for a certain response time). If the PT100 sensor is incorrectly connected (open circuit or short circuit), the relay drops out and the three LEDs flash.

HT81-2: Same function as above except with 2 relay outputs.

HWT81: As long as the temperature that is controlled by the PT100 sensor is between the two limit values, which are preset at the front, the relay output is activated and the yellow LEDs are on. When the temperature passes one of the set limit values (upper or lower), the time delay (Tt) is activated, which is also set at the front. The yellow LED R1 for temperature flashes. Once the delay has passed, the relay drops out and the LED turns off if the temperature still exceeds the set limit values. The relay output R1 activates immediately as soon as the temperature is between the preset limit values.

The relay also monitors the phase sequence L1, L2 and L3 in the 3-phase network as well as total phase interruption, even during regeneration (returned voltage) of the phase (<70 %). After an activation delay and for as long as no phase faults exist, R2 is activated and the LED R2 turns on. When a fault occurs, the relay drops out and the LED R2 turns off. Once the fault is corrected, the relay re-activates and the LED R2 turns on again. If the PT100 sensor is incorrectly connected (open circuit or short circuit), the relay output R1 deactivates and the LED R1 flashes.

Part numbers

Parts Price Measurement range Output
Relay 1 pole C/O
Fasövervakning 208-480V AC 2x Relay
2x Relay

Part

Control relay

84874110
OBSOLETE PRODUCT

Technical data

Approvals CSA, GL, RoHS, UL
Breaking capacity 5A, 250V AC/DC
Function Under/Overtemperature
IP class connection IP20
IP class housing IP30
Lower limit -1 - 11°C
Output Relay 1 pole C/O
Sensor cable length max 10 m
Storage temperature max 70 °C
Storage temperature min -40 °C
Supply voltage 24-240V ac/dc
Temperature operational max 50 °C
Temperature operational min -20 °C
Time delay startup 0,2 s
Time delay when exceeding the limit value 1-10s
Upper limit 34 - 46°C
Weight 121 g

Measurements and connections

  • HT81<br />1: F1: Fast-blow fuse 1 A (recommended)

    HT81
    1: F1: Fast-blow fuse 1 A (recommended)

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