Pepper Computer RS232, RS485 user manual Sm-Therm

Chapter 5 Analog Modules SMART I/O User’s Manual

5.3SM-THERM

5.3.1Introduction

The SM-THERM supports up to four groups of thermoelement sensors together with a cold junction (ext. PT100) for accurate temperature measure- ment. The sensor types shown in the table below may be connected with corrective calibration for all sensor classes being provided by driver software running under OS-9. A fast 16-bit delta-sigma A/D converter ensures an absolute accuracy of 0.2°C.

5.3.2 Specifications

Isolation	1.0 kV Optoisolated from the system
	4 Thermocouple groups
	1 PT100 for Cold Junction (2-wire)
	Open Sensor Detection
	Self Calibration			: ± 25V (power connected)
	Overvoltage Protection
				: ± 35V (power disconnected)
Input	Temperature Range			: Refer to table below
	Temperature Drift			: 1 LSB/°C (not compensated)
	Conversion Time			: typ. 125 ms, max. 500 ms
				(depends on filter settings)
	Input Impedance			: 10 M Ω (min)
	Resolution			: 16-bit
	Absolute Accuracy			: ± 0.2°C (sensor errors excluded)
	Linearization			: by software
EEPROM	256-bit serial EEPROM for Calibration Data
Front Panel	2 Red LEDs
Power Cons.	350mW (min.), 450mW (max.)
Temperature Range	Standard (0°C to +70°C), Extended (-40°C to +85°C)
Module Weight	40g
ID Byte	$61, read by the SPI Interface
Sensor Category Temperatur e Temperatur e Sensor			Category Temperatur e Temperatur e
(Low Range) (High Range)				(Low Range) (High Range)
R	-50°C	1760°C	T	-270°C	400°C
S	-50°C	1760°C	E	-270°C	1000°C
B	0°C	1820°C	K	-270°C	1370°C
J	-210°C	1200°C

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March 12, 1996 ©1996 PEP Modular Computers GmbH Page 5 - 59