Yamatake SDC35/36 Controller Application Guide

Yamatake SDC35/36 Single Loop Controller Engineering Application and Debugging Manual

In the field of industrial process control, single loop digital regulators are still the main instruments for temperature/process control in heat treatment furnaces, plastic machinery, environmental testing chambers, packaging equipment, etc., due to their high reliability, fast response, and easy operation. The DigitroniK series SDC35/36 controller from Yamatake (now part of Azbil Group) in Japan has won a wide market with its compact design (panel depth of only 65mm), high precision (± 0.1% FS), and advanced PID algorithm "Rational LOOP+Just FITTER". This controller supports thermocouples RTD、 Multiple range inputs such as current and voltage, can be freely combined with up to two control outputs (relay, voltage pulse, continuous voltage, current), and can be optionally equipped with event output, CT input, etc DI、 Remote Set Point (RSP) and RS-485 communication. This article will provide a comprehensive engineering practice guide for automation engineers, covering hardware selection, installation and wiring, parameter tuning, event diagnosis, and maintenance troubleshooting.

Product positioning and core advantages

The main difference between SDC35 and SDC36 lies in their external dimensions (48 × 48 mm for SDC35 and 96 × 96 mm for SDC36) and differences in some I/O points, but their core control performance is completely consistent. Its prominent features include:

Ultra thin design: The depth behind the panel is only 65mm, and the thickness of the front panel is 5mm, suitable for control cabinets with tight space.

High precision and fast sampling: With an indication accuracy of ± 0.1% FS and a sampling period of 100ms, it can capture rapid temperature fluctuations.

Multi range input: The same device can be freely set to TC (26 types including K, J, E, T, R, S, B, N, etc.) RTD（Pt100、JPt100）、 DC current (0-20mA, 4-20mA) or DC voltage (0-5V, 1-5V, 0-10V, etc.) greatly simplifies spare parts inventory.

Advanced PID algorithm: Rational LOOP combined with Just FITTER technology effectively suppresses overshoot, responds quickly to external disturbances, and supports up to 8 sets of PID parameters.

Flexible output combination: Control outputs 1 and 2 can be selected from relays (SPST or SPDT), voltage pulses (SSR drive), currents (0-20mA/4-20mA), or continuous voltages (0-5V/1-5V/0-10V), respectively, to achieve dual output control for heating/cooling.

Rich auxiliary I/O: up to 3 event relays, 2 CT (current transformer) inputs, 4 digital inputs (DI), remote set point (RSP) inputs, and RS-485 Modbus communication.

Intelligent loading software: Parameter configuration, real-time monitoring, and data recording are carried out through the SLP-C35 software package (Smart Loader Package).

Detailed explanation of technical specifications

2.1 Input (PV) specifications

Project parameters

Input type thermocouple (K, J, E, T, R, S, B, N, PLII, Wre5-26, Ni NiMo, PR40-20, DIN U/L, gold iron chromium nickel, etc.), RTD (Pt100/JPt100), DC current (0-20mA/4-20mA), DC voltage (0-10mV, 0-10mV, 0-1V, 0-5V, 1-5V, 0-10V)

Sampling period of 100 ms

Input impedance voltage input ≥ 1M Ω; current input ≤ 100 Ω

Broken thermocouple/RTD: upper limit beyond range+AL01 display; Voltage/current: can be set as lower or upper limit, please note that wire breakage cannot be detected within the range of 0-10V and 0-20mA

Cold end compensation accuracy ± 0.5 ℃ (23 ± 2 ℃ environment), ± 1.0 ℃ (15-35 ℃), ± 1.5 ℃ (0-15 ℃ or 35-50 ℃)

Indication accuracy ± 0.1% FS ± 1 digit; The negative temperature range of the thermocouple is ± 0.2% FS ± 1 digit (23 ± 2 ℃)

Engineering points: For B-type thermocouples (0-1800 ℃), the accuracy is ± 4.0% FS below 260 ℃, so B-type thermocouples should not be used in low-temperature areas; The accuracy of R/S type below 100 ℃ is ± 0.2% FS.

2.2 Control output specifications

The controller provides up to two control outputs (depending on the model), with optional types:

Applicable scenarios for output type specifications

Relay contact (SPST) control output 1 (NO side): 250Vac/30VDC, 3A (resistive), lifespan ≥ 50000 times; Control output 2 (NC side): 1A, lifespan ≥ 100000 times, directly drive contactor and heater

Motor driven relay dual circuit relay (forward and reverse), 250Vac 8A, used for electric valve position control and valve position adjustment

Voltage pulse 19Vdc ± 15%, internal resistance 82 Ω, maximum 24mA, minimum pulse width 1ms (period ≤ 10s) or 250ms (period>10s) to drive solid-state relay (SSR)

Current output 0-20mA/4-20mA, load ≤ 600 Ω, accuracy ± 0.1% FS, resolution 1/10000, driving thyristor power regulator and frequency converter

Continuous voltage 0-5V/1-5V/0-10V, load ≥ 1k Ω, accuracy ± 0.1% FS driven analog input actuator

Attention: When using voltage pulse output, the cycle time can be set within the range of 0.1-20 seconds (≤ 10s cycle) or 5-120 seconds (>10s cycle) to match different types of SSRs.

2.3 Auxiliary functions

Event output: up to 3 independent relay contacts (250Vac/30VDC, 2A). Programmable for PV high/low limit, deviation high/low limit, MV high/low limit, Loop Diagnosis 1/2/3, timer, RSP status, AT status, etc.