Difference Setpoint Control - On/Off Zoom

Difference Setpoint Control - On/Off


Brand: Tekmar

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Application: Alternative Energy
Width: 2-7/8"
Height: 4-3/4"
Difference Setpoint
User Interface: Push Button
Depth (Inches): 7/8"
Ambient Conditions: Indoor Only: -20°-120°F < 90% RH non-condensing
Power Supply: 24V (ac)
24V (dc)
Relays: 240 V (ac) 10 A-1/3 hp-pilot duty 240 VA
Max Temp (F): 284°F
Min Temp (F): -76°F
Temperature Range (F): -76°-284°F
Control: Microprocessor Control
Weight (lbs): .7 lbs
Sensors: NTC Thermistor
10 k ohm @ 77°F
Enclosure Type: C

Description for Tekmar 156

Control Description The Difference Setpoint Control 156 is designed to operate an on/off pump to transfer heat from a heat source to a storage tank. The control operates based on a setpoint temperature difference (ΔT). The relay turns on when the ΔT rises above the setpoint and turns off when the ΔT falls below the setpoint less the differential. The Source Minimum and Storage Maximum settings turn off the relay when heat transfer is no longer desirable. Potential applications include using solar collectors or a wood boiler as a heat source.

LiteratureD 156, A 156, D 001, D 070
ControlMicroprocessor control; This is not a safety (limit) control
Packaged Weight0.8 lb. (360 g)
Enclosure C, White PVC plastic
Dimensions4-3/4" H x 2-7/8" W x 7/8" D (120 x 74 x 22 mm)
ApprovalsCSA certified to CSA 22.2 No 24 and UL 873
Ambient ConditionsIndoor use only, -20 to 120¼F (-30 to 50¼C), < 90% RH non-condensing
Power Supply24 V ¼10% 50/60 Hz 2 VA
24 V (dc) ¼10% 0.04 A
RelayRelay 240 V (ac) 10 A 1/3 hp, pilot duty 240 VA
Sensors IncludedNTC thermistor, 10 kΩ @ 77¼F (25¼C ¼0.2¼C) +=3892 Two of Universal Sensor 071

Difference Setpoint Control - On/Off


by PowerReviews
TekmarDifference Setpoint Control - On/Off

(based on 2 reviews)

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Works good

By BrnmccO1

from Indiana, USA

Verified Reviewer



      Best Uses

        Comments about Difference Setpoint Control - On/Off:

        Using with a solar evacuated tube system

        • Primary use:
        • Business

        Tekmar 156 does it all

        By Scott

        from Blanchardville, WI.

        Verified Buyer



            Best Uses

              Comments about Difference Setpoint Control - On/Off:

              The Tekmar 156 is the perfect control for a home based solar water heating system. Mounted next to my house thermostat, the read-outs tell me everything I want to know about how my system is operating, and at the same time completely automating the control of my circulating pump for maximum efficiency. Once installed, you just sit back and let the control run the system.

              • Primary use:
              • Personal

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              • Difference Setpoint Control - On/Off


                does product include sensors?
                Asked on 2/24/2011 by Kevin from Canada

                1 answer

                • CUSTOMER CARE


                  Yes, it includes Solar Sensor 085 and Universal Sensor 071.

                  Answered on 2/25/2011 by PexSupply Staff from NY
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