Michell Instruments XZR500ST, User Manual

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XZR500 User’s Manual
16 97137 Issue 8, April 2017
OPERATION
3 OPERATION
The MSRS is a fragile element - keep the sensor free from any
shock. Any measurements that need to be done at the MSRS
terminals must be done very carefully in order to prevent
irreversible damage to the sensor.
NEVER attempt to measure the resistance between the MSRS
reference terminal and another terminal
Use a voltmeter with impedance >1000 M Ω for measuring
the voltage between the MSRS measurement and reference
terminals
3.1 Outputs
3.1.1 Analog Output
The output signal is selectable to be either 0-20 mA or 4-20 mA.
The range is selectable between 0 and 25%.
3.1.2 Alarms
The system has 3 alarm contacts:
• 1 general failure alarm warning of furnace under temperature (20°C
below the set temperature), thermocouple separation, problem with RAM
backup after a re-set or adjustment error.
• 2 threshold alarms, with programmable activation direction and hysteresis.
The activation of a threshold alarm can be identi fi ed when the corresponding green LED
turns off on the Control Unit.
The activation of the general fault alarm can be identi fi ed when all the three green LEDs
turn off on the Control Unit.
The contacts are normally closed, dry and potential-free. The maximum switched load
is 10 W for each contact (up to 100 V or up to 0.5 A).