EpiTemp Duo Temperature Controller (ET20)


  • Precision temperature controller specifically designed for deposition sources
  • 2 channels. Can be used independently or in cascade arrangement
  • 3 port isolation for each channel
  • Half-rack 1U unit. Simple to install.
  • Standard thermocouple and output connectors
  • Precision temperature & CJC measurement
  • raPID 3 zone PID algorithm with overshoot control
  • Gentle multi-step auto-tuning for precise PID evaluation
  • Inputs: Range of thermocouple, µV and user-defined scaled
  • Voltage and current loop output as standard
  • User programmable (single resistor) output conditioning
  • Fast, efficient, floating-point resolution MODBUS data transfer

EpiTemp Duo Description

The EpiTemp Duo is a high precision, high stability, dual channel temperature controller specifically designed for applications requiring accurate control (e.g. MBE).

Housed in a half-width 1U high 19" rack mounting enclosure, the Duo offers high controller density (4 channels per 1U space); single and double mounting hardware kits are supplied with the controller. Use of standard thermocouple connectors and DB15 output connectors makes for easy installation.

The performance of the Duo has been optimised for deposition applications and includes features such as support for most common thermocouple types, multiple PID zoning, floating point temperature control resolution (2 dps display), dynamic sample rate operation, overshoot protection, gentle auto-tuning, ramping, user-defined power-up definition etc.  

Voltage (0-10V) AND current-loop (0-26mA) outputs with user-defined output conditioning are supplied as standard, as are 2x digital input, 2x digital output interlocks and multi-drop RS232 and RS485 interfaces.

The unit can either be manually controlled, or from computer via the MODBUS protocol featuring floating point resolution data transfer and multi-parameter send and receive within a single message for fast multiple unit communications.

EpiTemp Duo Specification


Dimensions1U high, half 19" rack mounting.
Depth 210mm excluding connectors
Weight: 1kg
Power230/115Vac (+10-15%) - rear panel selected
Typical 3VA
Display2x16 character alpha-numeric
UnitsUser-defined. Temperature: °C, °F or K. Voltage: µV. User-defined: AU


Configuration2 independent precision temperature channels
Optional cascade (master/slave) configuration
IsolationIsolated channels
Per Channel: three-port isolation between input amplifier, processor and output + conditioner stage. All up to ±50V with respect to earth
Power upUser-defined selection: control at measured temperature, user-defined temperature or user-defined power
Channel NamingUser-defined name per channel (up to 4 ASCII characters)


OptionsThermocouple types: C,J,K,N,E,S,T.
Voltage input in µV.
User-defined scaled input
ConnectionsStandard mini-thermocouple connectors with embedded CJC sensors
Input Range+90mV to -18mV. Up-scale sensor break
MeasurementTemperature: <<0.01°C all types
Voltage: << 0.1µV
User-definable (arbitrary units). Positive input range can be scaled to give an input range of from 0 to 1.000 to 0 to 1000000.
Resolution9 or more significant digits
Display: 0, 1 or 2 decimal places
Comms: 32-bit floating point resolution
FilteringHardware: >12dB/decade at 10Hz
Software: User selectable low pass & discrete sample (spike removal)
Cold Junction Sensor10-50°C range.
Initial calibration error @25°C < ±0.2°C
Internal rejection >>30:1
CJC typesUser-selected: measured, off or fixed temperature (ice-point) reference (±99.0°C)

      Control Action

PIDraPID algorithm: PID, PI, PD, P or "manual" power. "Damp" over-shoot rejection.
Zoning3 user-defined zones. Bump-less transitions between zones
PID RangeP: 0.01 to 999.99 Engineering Units
I&D: 0.1 to 999.9 seconds
Damp: -0.1 (AUTO), 0.0 (OFF) or user value up to 9. Arbitrary units.
Auto-TuneGentle multi-step adaptive relay feedback method
RampInstant change or 99.00 to 0.01degrees/second


ConnectorDB15 socket (shared both channels, digital inputs and outputs)
Resolution12 bit. Linearity < 1bit
OutputsVoltage: 0-10V @ 10mA source/sink
Current loop: 0-26mA
ConditionerPermits V and I output range to be user-defined using single resistor

      Digital Inputs

Number2 total: 1 per channel
TypeOpto-isolated with input R = 4k7Ω (4-40V)
User functionalityInterlock, go to temperature/power, time delay setting...

      Digital Outputs

Number2 total: 1 per channel
TypeOpto-isolated open-collector transistor (isolation: 1kV). Rated at 30mA @ 30V. Reverse polarity protected
User functionalityInterlock (temp ±limit, outside hysteresis level).
Comms based on/off (e.g. MBE shutter operation)


SerialMulti-drop RS232 and RS485 as standard
ProtocolMODBUS. Floating point data transfer. Multi-parameter read and write in single message