Electronic Remote Controller with On/off control and 3 Spdt relay outputs
The T775 family of electronic remote temperature controllers provide on/off, modulating, or reset control in applications where electronic accuracy in addition to remote sensing is desired.
Available with one or two temperature inputs and up to four spdt relay output stages or modulating (electronic Series 90, 4-20 mA or 0-18 Vdc) outputs.
Typical applications include:-on/off control of fans, motors and heaters.-proportional and floating control of damper and valve actuators.-outdoor reset of heating and cooling systems.
Electronic control accuracy.
Linear platinum temperature sensor.
LCD display indicates mode and output status; jumper switch provides field selection of F or C display.
Keypad allows precise temperature selection; easy one-finger programming.
Remote sensing from up to 1000 ft. (304m).
Wide temperature setting range.
Adjustable differential and throttling range.
Heating and cooling stages independently programmable.
Available with NEMA 4X enclosure.
Optional No. 203531A Panel Mounting Kit allows mounting in an electrical panel.
Available Application Guide, form no. 63-1197, offer answers to common application questions.
Frequently Asked Questions:
Q: Can the switching differential be set wider than 35
A: Yes. Convert the T775 to the Celcius scale by removing the jumper at the top right on the circuit board. The differential setting can now be 35
•C, i.e. 63
•F. Note that setpoints programmed in Farenheit will not be converted to
•C. In other words, 70
•F becomes 70
•C after scale conversion, therefore requiring reprogramming of the unit to maintain original setpoints.
Q: Does the T775 save programmed values if the power is lost
A: Yes. The T775 has an EEPROM that saves all values entered and restores them once power is reapplied.
Q: When an output stage is changed from a heating to cooling load, do any program values change
A: Yes. The setpoint for that stage will remain the same but the switching differential or throttling range (depending on the type of output) will default back to its default value. This parameter will need to be re-programmed.
Q: Why do setpoints 2,3 & 4 change when a change is made to setpoint 1
A: After initial programming, altering the setpoint for stage 1 up or down will result in a change in setpoints 2,3,& 4 by the same number of degrees and in the same direction. However, changing stages 2, 3, or 4 only changes the value for that particular stage - no other setpoints will change.
Q: How is the reset ratio entered for the T775J
A: The reset ratio is entered in two parts: The numerator and the denominator. The T775 reset ratio represents the change in outside temperature (the numerator) to the change in indoor control temperature (the denominator). On the display, the numerator is called the RESET RATIO B and the denominator is RESET RATIO A. The desired value for each part of the ratio should be entered using normal programming techniques.
Q: Must the RESET RATIO be reduced to some value to 1
A: No. As long as the B and A values are between 1 and 30 any value can be used.
Q: How are the setpoints defined in the T775
A: "Setpoint" is typically defined as where the load comes on. For example, the T874 turns on the heat when the room temperature falls to the setpoint.
The T775 defines the setpoint as the point where the load goes off. For example, stage 1 heat is turned on when the temperature falls below the setpoint and through the differential.
Application On/off control for applications where electronic accuracy and remote sensing is required
Type Electronic remote bulb
Setpoint Temperature Range (F) -40 F to +220 F
Setpoint Temperature Range (C) -40 C to +105 C
Output Type relay
Output 3 spdt
Voltage 24 Vac or 120 Vac or 240 Vac
Frequency 60 Hz;50 Hz
Contact Ratings (24 Vac) 10.0A resistive
Contact Ratings (120 Vac) 9.8 AFL, 58.8 ALR, 125 VA Pilot Duty
Contact Ratings (240 Vac) 4.9 AFL, 29.4 ALR, 125 VA Pilot Duty
Dimensions (in.) 8 1/2 in. high x 4 3/4 in. wide x 2 3/8 in. deep
Dimensions (mm) 216 mm high x 121 mm wide x 61 mm deep
Sensor Element Platinum Sensor
Number of sensors 1
Maximum distance to sensor (ft) up to 1000 ft.
Maximum distance to sensor (m) up to 304 m
Bulb Size (in.) 3/8 in. diameter x 2 5/8 in. long
Bulb Size (mm) 9.5 mm diameter x 67 mm long
Operating Temperature Range (F) -40 F to +125 F
Operating Temperature Range (C) -40 C to +52 C
•1 F at 77 F
•0.5 C at 25 C
Differential Temperature (F) 1 F to 35 F
Differential Temperature (C) 0.6 C to 19 C
Approvals, Underwriters Laboratories Inc File E4436, Vol. 19, Sec. 1, Guide XAPX
Approvals, Canadian Standards Association Certified: File No. LR95329
Replaces Part Numbers: