120Vac, 208-250Vac or 12/24Vac/dc, 50/60Hz ( specify model ) 2F to 22F ( 1C to 12C ) Other ranges upon request. 1F to 20F ( 1C to 11C ) Other ranges upon request. -16F to +208F (-26C to +98C) standard or depending upon temp. probe ordered (-50C to +250C temperature ranges AVAILABLE upon request ) +/- 1F (0.5C) Celsius or Fahrenheit (selectable) For Heating: LOAD ON when Temperature Difference Lower than "MIN" diff. preset LOAD OFF when Temperature Difference higher than "MAX" diff. preset For Cooling: LOAD ON when Temperature Difference Higher than "MAX" diff. preset LOAD OFF when Temperature Difference Lower than "MIN" diff. preset ( Other operating modes upon request ) 2 x 3 digits, 7 segment, Super Bright LED RED ( 0.36" LED display digits ) + POWER ON and LOAD ON indication Current Temperature on both probes and ON Diff. and OFF Diff. indication SPST relay, 30 Amp, 250Vac (or custom) SPST relay, 30 Amp, 250Vac (or custom) OPTIONAL, SPST relay, 10 Amp, 250Vac (or custom) OPTIONAL, SPST relay, 10 Amp, 250Vac (or custom) OPTIONAL, piezo, 85dB internal 2 PROBES up to 500 feet ( 150m ) away from controller ( any type wire ) Standard +208F (+98C ) high temp. limit ( other limits optional ) Automatic with error display and protection |
APPLICATIONS: SOLAR HEATING control SOLAR COOLING control VENTILATION control HUMIDITY control Air Conditioning HEATERS and CHILLERS Other media Temperature Heat /Cool process control |
Specifications: Supply: "MAX" Differential range: "MIN" Differential range: Temp. control range: Temp. Accuracy/units: Control mode: Display: Display Data: Load output 1: Load output 2: Load output 3: Load output 4: Alarm buzzer: Probe wiring: High Temp. protection: Error detection: |
series DSD-2RT Digital DIFFERENTIAL THERMOSTAT with 2 external temperature sensors. Output load up to 60 Amp / 250Vac with 2, 3 or 4 relays on-board with 2 ROTARY controls : 1. POWER ON/OFF and "OFF" Differential Preset 2. "ON" Differential Preset |
DIMENSIONS: Face: Stainless Steel with Lexan decal. Body: ( W x H x D ) 5-3/8" x 2.75" x 2" 136mm x 70mm x 51mm |
DESCRIPTION: Electronic, digital differential temperature controller designed for Solar Heating, Cooling, A/C, Ventilation, Humidity Control etc... The "ON" and "OFF" or "MIN" and "MAX" Temperature Difference can be preset by rotating the knobs on the face. The thermostat will control the output high power relays ( 1, 2, 3 or 4 relays on board ) that can be wired to a heater, fan, pump, A/C or other load. The output relays contacts are isolated for wiring to any low or high voltage loads.. The two digital displays show both probes temperature readings as well as the Differential presets. Models available for 120Vac, 208-250Vac, 12V or 24V AC/DC, 50/60Hz. Other Features: The probes may be wired up to 500 ft. ( 150 meters ) away from the controller. The differential presets may be adjusted at any time. Models with High and/or Low temperature limit are available as permanent or adjustable. The temperature probes can be wired up to 500 ft. ( 150m ) away from the controller with an ordinary 2-conductor cable Quiet, switching of high power loads. Celsius or Fahrenheit temperature units selectable. |
INSTALLATION in Box or Wall ( Panel ): Designed to fit in a 3-Gang electrical box or in a panel. Face plate will sit flush with the wall. |
Model: DSD-2RT-2D-2CH-2HP-120-56-FN16P208-IHL200F-DONP3P22F-DOFP1P20F-2NA7100KB4100BLK |
Differential Thermostat with rotary controls and 2 external probes included. Operating range: -16F to +208F (-26C to +98C ). IN High Temp. Limit = +200 F( +93C ). "MAX" Diff. preset range = 3F-22 F (2C-12C ). "MIN" Diff. preset range = 1F-20 F ( 1C-11C ). 2 High Power relays (30 Amp/250V max each). Option "2CH" = One relay for Heat and the other for A/C.or Fan. Either one or both can be used. |
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SELECTION of standard Temperature Probes : |
TYPICAL WIRING EXAMPLES ( click on images for more ) |
KERA Technologies Inc. Toll Free: 1-866-829-4253 |
NA7100KB4100BLK NA7100KB4100CHR NA7100KB4100RDT NA7100KB4100SQT NA7100KB4100DPD NA7100KB4100SHD PT1000TC38550MM NA7100KB4100PIPTR |
OPTIONAL Plastic or Metal (SS) Sensor Probe Plate (model PPP4 or PPS4 ). |
OPTIONAL: Sensor Probe Guard model PG5 (black or grey ) . |
COMPLETE NUMBERING SYSTEM FOR SD series CONTROLLERS : ( click below to download PDF document ) |
Toll Free: 1- 866- 829- 4253 |
For 2 AC / DC Motors, Pumps, Fans or other loads up to 2 x 30 Amp max. |
With contactor for Very High load Power |
Simple wiring for loads up to 30 Amp max. |
Model: DSD-2RT-1D-2SH-2HP-120-56-DON24F-IHL95F-H2F-FN16P208-2NA7100KB4100BLK |
Application Examples |
For Heating or Cooling, Attic / Roof Ventilation and Humidity Control: |
For Heating, Ventilation and Humidity Control in Switchgear (with High temp Limit
): |
Differential Thermostat with rotary controls and 2 external probes included. Operating range: -16F to +208F (-26C to +98C ). IN High Temp. Cut-Off Limit = +95 F( +35C ). "ON" Diff. preset range = 2F-24 F (1C-13C ). "OFF" Hysteresis = 2 F ( 1C ). 2 High Power relays (30 Amp/250V max each). Option "2SH" = Both relays close below "MIN" diff. and open above "MAX" diff. |
Differential Thermostat with rotary controls and 2 external probes included.
Operating range: -16F to +208F (-26C to +98C ). High Temp. Limit = +208 F( +98C ). Adjustable IN Low Temp. Cut-Off Limit +60F to +80 F( +16C to +27C ). Optional adjustable High Limit instead. "ON" Diff. preset range = 1-20 F (0.5-11C ). "OFF" Hysteresis = 1 F( 0.5C ). 2 High Power relays (30 Amp/250V max each). Option "2SC" = Both relays close above "MAX" diff. and open below "MIN" diff. |
Model: DSD-2RT-1DL-2SC-2HP-120-56-DON20F-ILLP60P80-H1F-FN16P208-2NA7100KB4100BLK |
For Cooling or Ventilation with adjustable Low (or High) Limit : |
For Solar Heating Control with selectable Low Temp Limit, High Temp Limit, Overheat Protection and Freeze Protection : |
Model: DSD-2RT-SOL-2HP-1MP-120-56-DONP2P22F-DOFP1P20F-OFRA-OLL-OHLR-FN16P208-2NA7100KB4100BLK |
Differential Thermostat with rotary controls and 2 external probes included. Operating range: -16F to +208F (-26C to +98C ). ( other values on request ) "ON" Diff. preset range = 2F-22 F (1C-12C ). "OFF" Diff. preset range = 1F-20 F (0.5C-11C ). Selectable OUT Low Temp. Cut-Off Limit at +68 F ( +20C ). ( other values on request ) Selectable OUT Freeze Protection Auto Circulation ON at +42 F ( +5.5C ) ( other values on request ) Selectable OUT High Temp. Protection at +190 F( +87C ). Activates 3-rd relay. ( other values on request ) 2 High Power relays (30 Amp/250V max each), SPST each for 1 or 2 Circulating Pumps. 1 Medium Power relay (10 Amp/250V max), SPST. for OUT Overheat Protection. |
NOTE: CUSTOM MODIFICATIONS AVAILABLE FOR ALL
MODELS |
For Heating and Air Conditioning : |
Model: DSD-2RT-2DACH-2HP-120-56-DONN4P12F-DOFN4P12F-H1F-FN16P208-2NA7100KB4100BLK |
Differential Thermostat with rotary controls and 2 external probes included. Operating range: -16F to +208F (-26C to +98C ). High Temp. Limit = + 208 F( +98C ). Cooling: "ON" Diff. preset range = -4F to +12 F (-2C to +6C ). Hysteresis = 1F. Heating: "ON" Diff. preset range = -4F to +12 F (-2C to +6C ). Hysteresis = 1F. 2 High Power relays (30 Amp/250V max each). One for Heat and One for A/C. Either one or both can be used. This controller may be used to make the temperature in one area follow another area with adjustable offset. |
Thermowell model: BTW-100-05-075NPT Brass, Stem = 4" , Bore = 0.2", 3/4 NPT thread |
Thermowell model: BTW-25-05-075NPT Brass, Stem = 1" , Bore = 0.2", 3/4 NPT thread |
Thermowell model: BTW-25-05-025NPT Brass, Stem = 1" , Bore = 0.2", 1/4 NPT thread |
Solar Heating, Attic / Roof Ventilation, Switchgear Humidity prevention
|
- Hight Temp. Limit - Low Temp. Limit - ON and OFF Differential Preset - Freeze Protection - Overheat Protection - Alarm Buzzer |
OPTIONS: |
House Attic / Roof ventilation |
Fan |
Inside Sensor |
Outside Sensor |
Switchgear humidity control or ventilation |
Inside Sensor |
Outside Sensor |
Heater or Fan |
Thermowell model: SSTW-114-066-050NPT |
Stainless Steel Stem = 1-5/8" Bore = 0.26" 1/2 NPT thread |
Stainless Steel Stem = 4-1/2" Bore = 0.26" 1/2 NPT thread |
Thermowell model: SSTW-41-066-050NPT |
Thermowell model: SSTW-64-066-050NPT |
Stainless Steel Stem = 2-1/2" Bore = 0.26" 1/2 NPT thread |
Thermowell model: SSTW-114-066-075NPT |
Stainless Steel Stem = 4-1/2" Bore = 0.26" 3/4 NPT thread |
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Heat Exchanger |
Solar Collector |
Water Tank |
DSD Controller |
Pump |
Pump |
Drainback Reservoir |
Hot Water Out |
Cold Water In |
Glycol |
Water |
Coax Cross Adapter |
Optional Overheat Valve |
FOR MORE SOLAR HEATING EXAMPLES CLICK HERE |
Simple split drainback system with external heat exchanger and one standard tank. |
Split pressurized system with a storage tank with internal heat exchanger and a service
tank with electric booster. |
Simple split pressurized system with one tank with internal heat exchanger. |
Split pressurized system with external heat exchanger and one tank with electric
booster. |
Split pressurized system with a storage tank with internal heat exchanger and a service
tank with gas booster. |
Hot Water Out |
Hot Water Out |
Hot Water Out |
Hot Water Out |
Cold Water In |
Cold Water In |
Cold Water In |
Cold Water In |
Compensation Tank |
Compensation Tank |
Compensation Tank |
Compensation Tank |
Solar Collector |
Solar Collector |
Solar Collector |
Solar Collector |
Optional |
DSD Controller |
DSD Controller |
DSD Controller |
DSD Controller |
Heat Exchanger |
Coax Cross Adapter |
Water Tank |
Water Tank |
Storage Tank |
Electric Service Tank |
Storage Tank |
Gas Service Tank |
Optional Overheat Valve |
Water |
Water |
Water |
Glycol |
Glycol |
Glycol |
Glycol |
Electric Booster |
Gas Booster |
Optional Overheat Valve |
Pump |
Pump |
Pump |
Pump |
Pump |
OPTIONAL WT-805 Tank Controller |
Electric Booster |
Optional Overheat Valve |
P/T Valves |
P/T Valve |
P/T Valve |
P/T Valve |
P/T Valves |
P/T Valve |
P/T Valve |
P/T Valve |
P/T Valve |
Solar Panel Temp. Probe |
Solar Panel Temp. Probe |
Solar Panel Temp. Probe |
Solar Panel Temp. Probe |
Solar Panel Temp. Probe |
Tank Temp. Probe |
Tank Temp. Probe |
Tank Temp. Probe |
Tank Temp. Probe |
Tank Temp. Probe |
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For 2 AC / DC Motors, Pumps, Fans or other loads up to 2 x 30 Amp max. and 1 additional Relay ( up to 10 Amp ) for Overheat or Freeze protection |
TEMPERATURE PROBE WIRING EXTENDABLE UP TO 500 FEET ( 150m ). |
CUSTOM TEMPERATURE RANGES PER REQUEST |
E-mail: info@keracontrols.com |
E-mail: info@keracontrols.com |
OPTIONAL WT-805 Tank Controller |
OPTIONAL WT-805 Tank Controller |
= Both relays close below "MIN" diff. and open above "MAX" diff. Most often
used for Heating. OUT cooler than IN. = Both relays close above "MAX" diff. and open below "MIN" diff. Most often used for A/C and cooling Fan. OUT cooler than IN. = One relay closes below "MIN" diff. and opens above "MAX" diff. and the other relay closes above "MAX" diff. and opens below "MIN" diff. OUT cooler than IN. This model may be used when it is not sure if cooling ( or ventilation ) or heating will be required, or in some more complex applications. = Similar to 2SH and 2SC except that only 1 relay is installed instead of 2. This is helpful when a lower supply power cons. is required. = Similar to above, except IN is cooler than OUT. Normaly the same can be achieved by swapping the probes locations, however then the IN - OUT labelling on the face will become reversed. = One differential adjustable only, called "ON" differential. The "OFF" differential is calculated automatically as the (ON diff.) + Hysteresis . The Hysteresis value is usually permanently set in the controller. = The Hysteresis value, usually permanently set in the controller that has one adjustable differential only, called "ON" differential. The "OFF" differential is calculated automatically as the (ON diff.) + Hysteresis . The "xx" in degrees Fahrenheit ( or C for Celsius ). = One differential adjustable only ( with Hysteresis ) and adjustable Low Temperature Limit also installed. = One differential adjustable only ( with Hysteresis ) and adjustable High Temperature Limit also installed. = Two differentials "MAXimum" and "MINimum" are adjustable separately. The controller will make sure that the span between them is maintained correctly. = ABSOLUTE differential mode of operation. The load is controlled irregardless if one probe is warmer or cooler than the other. = Two differentials "ON HEAT" and "ON COOL" are adjustable separately, one for Heating and the other for Cooling. The two relays will control heating and cooling respectively. This model will cause one area temperature to follow the temperature changes in another area within adjustable offsets. = Solar Control Differential mode. Includes Freeze, Low and High temperature protections and has 2 adjustable differentials and 2 or 3 relays on-board. = ALL OFF, Low Limit on IN temperature set permanently to "xx" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, Low Limit on IN temperature Adjustable from "xx" to "yy" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, Low Limit on OUT temperature set permanently to "xx" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, High Limit on BOTH temperatures set permanently to "xx" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, High Limit on IN temperature set permanently to "xx" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, High Limit on IN temperature Adjustable from "xx" to "yy" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, High Limit on OUT temperature set permanently to "xx" degrees Fahrenheit ( or C for Celsius ). = ALL OFF, High Limit on BOTH temperatures set permanently to "xx" degrees Fahrenheit ( or C for Celsius ) = High Limit on OUT temperature set permanently to "xx" degrees Fahrenheit ( or C for Celsius ) and driving a relay when limit detected. = High Limit on OUT temperature adjustable from "xx" to "yy" degrees Fahrenheit ( or C for Celsius ) and driving a relay when limit detected. |
Option "2SH" Option "2SC" Option "2CH" Options "1SH" and "1SC" Options 2ISH, 2ISC, 2ICH, 1ISH, 1ISC Option "1D" Option "HxxF" Option "1DL" Option "1DH" Option "2D" Option "ABS" Option "2DACH" Option "SOL" Option "ILLxxF" Option "ILLPxxPyyF" Option "OLLxxF" Option "BLLxxF" or "LLxxF" Option "IHLxxF" Option "IHLPxxPyyF" Option "OHLxxF" Option "BHLxxF" or "HLxxF" Option "OHLRxxF" Option "OHLRPxxPyyF" |
NOTE: Our DSD-2 Differential Thermostat model numbers are fully descriptive You DO NOT HAVE TO know the complete model number to order. Please call our customer service and we will assign a correct model number for your application. A short description of your application will be very helpful. For further reference, below are some additional options numbers used in the series DSD-2 thermostats numbering system: NOTE1: In the description of differential thermostats the designation "IN" and "OUT" is only symbolic, and it does not necessarily mean that the "IN" probe has to be "Inside" and the other " Outside". The sensor probes can be swapped by placing them in opposite locations in order to satisfy the correct control operation. However, remember that the temperature of the probe that is connected to the "IN" terminals wil be indicated on the "IN" section of the display and the probe connected to the "OUT" terminals wil be indicated on the "OUT" section of the display, and the controller operation will behave accordingly. NOTE 2: In many cases the DSD-2 thermostats may be ordered with more than one option. For example, it is possible to order the model DSD-2RT-2D-2SH... |