Signal Consulting, LLC 

Model Si82Di2ZPTC 

 9-Bit, Digital Two-Zone Proportional Temperature Controller with Two AC 120/240V-5A Solid-State Relays, 4-Keys and one LCD Port, Y-Chip





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Si82Di2ZPTC Features:

Efficient Two-Zone Proportional Temperature  Controller in   the range of +50C to +1020C with 1/20C Steps

An LCD port (with HITACHI HD44780 Interface Standard) for Set and Measured Temperature Display.
Two 120/240V, 5A AC Solid-State Relays for Heaters
Two Digital Thermometer  with 1/20C Accuracy
Two Sets of Onboard  Up and Down Set-Temperature Keys

High Power-Efficiency: 98.5% typical, at 120V and 5A

On Board:
Rectifier and Filter Capacitors
VTS diodes
Two LEDs as Heater-On Indicators (one for each zone)

Voltage Requirement:
A single (9V to 20V) AC or DC Voltage (unregulated and Unfiltered) for Board-Control Voltage

Si82Di2ZPTC  Spec Sheet  (PDF)

The Si82Di2ZPTC-120/240Vac-5A is a versatile, closed-loop, microprocessor based, Digital, Two-Zone, Proportional Temperature Controller board that can control two independent thermal-zones. By proportional control, we mean that the amount of correction used in the closed-loop is proportional to the difference between the set and measured temperature values. Five PWM duty-cycle values are used depending on the absolute-value of the difference between the set and measured temperature values (|Td|). The duty-cycle is 0% when |Td|=00C; 25% when 00C< |Td|<0.50C; 50% when 0.50C< |Td|<10C; 75% when 10C< |Td|<1.50C; 100% when |Td|>1.50C.  Two120/240Vac, 5A solid-state relays (one for each zone) are used to control the currents in resistive heaters (600W in each zone). A single AC or DC voltage source (9V to 20V rang, unregulated and unfiltered) is required for the control electronics. The onboard microprocessor measures and controls the temperatures, and monitors the user inputs. Two small 9-bit digital thermometers (by Dallas Semi., DS18S20 sensor, connected to ports CN4TS1 and CN5TS2) are used to measure temperatures in the +50C to +1020C range, with 0 C accuracy. Because each sensor is digital, it is virtually immune to noise and loading; ideally suited for remote sensing. This sensor uses a unique “1-wire interface” (with parasite power mode) that requires only 2-conductors for reliable remote (long as 20 meters) temperature sensing. As the name Digital (Di) implies the desired set-temperatures are derived from board-mounted push-button type Up or Down keys while the other control signals are also digital. An LCD port (with HITACHI HD44780 Interface Standard) is provided for optional display of Set and Measured Temperatures data in 2 line x 20 character format. Two red LEDs are used to monitor the Heater currents. A small Aluminum plate (3.3”x4.0”x0.065”) is required to operate at 2x600W power level. Typical applications are: Dual Water-Baths, 2-Zone Heat-Pumps, etc. This board can be configured and programmed to perform efficiently in many customized applications. 

A Typical Application of the Si82Di2ZPTC-120/240Vac-5A

In this closed-loop proportional temperature control application, the Set-Temperature (in the, +50C to +1020C Range with 1/20C steps) is adjusted (for each zone) by the board-mounted Up and Down keys. The resistive Heaters are operating with 120Vac at 5A max. A small transformer with 12Vac output provides the control-power to this board. The temperature in each zone is measured with the Dallas Semi.  (DS18S20 in TO-92 casing) Digital Thermometer. This sensor can be purchased from Signal Consulting, LLC as Si18DTsens (sensor with 12” leads and connector) or you can wire-up your own sensor using parts from . The LCD module can be purchased from Signal as Si24LCD2L20CH, or from several vendors; for OEM pricing, contact: Sunlike Display Tech Corp. in Taiwan, .


Si82Di2ZPTC , Digital 2-Zone  Proportional Temperature Controller
Price $169.00

Note: If Buying the Si82Di2ZPTC, it is recommended to buy one  Si600APHS1 Heat Sink, two Si18DTsens  9-bit Digital Thermometers and one Si24LC2L20CH  2 Line by 20 Character LCD.

Si600APHS1  Heat Sink (3.3"x4.0"x.065" Alum. Plate) with .375" Standoffs and 4-40 screws.
Price $12.00
Si18DTsens  9-bit Digital Thermometer ( -400C to +1400C Range, in 1/20C Steps) with 12" leads and 3pin FM connector.
Price $29.00
Si24LC2L20CH  2 Line by 20 Character LCD with 8" long ribbon cable and 14-pin connectors.  
Price $59.00

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Availability: We usually ship in 2-3 business days.



All Products Are Proudly Made in the USA