Instruction manual

2 5 Sensor Installation Guidelines
Proper sensor installation can eliminate many problems in a control system.
The probe should be placed so that it can detect any temperature change
with minimal thermal lag. In a process that requires fairly constant heat
output, the probe should be placed close to the heater. In a process where
the heat demand is variable, the probe should be close to the work area.
Some experiments with probe location are often required to find this
optimum position.
In a liquid process, addition of a stirrer will help to eliminate thermal lag.
Since the thermocouple is basically a point measuring device, placing more
than one thermocouple in parallel can provide an average temperature
readout and produce better results in most air heated processes.
Proper sensor type is also a very important factor to obtain precise
measurements. The sensor must have the correct temperature range to
meet the process requirements. In special processes the sensor might need
to have different requirements such as leak-proof, anti-vibration, antiseptic,
etc.
Standard sensor limits of error are 4 F ( 2 C) or 0.75% of sensed
temperature (half that for special) plus drift caused by improper protection or
Proper sensor installation can eliminate many problems in a control system.
The probe should be placed so that it can detect any temperature change
with minimal thermal lag. In a process that requires fairly constant heat
output, the probe should be placed close to the heater. In a process where
the heat demand is variable, the probe should be close to the work area.
Some experiments with probe location are often required to find this
optimum position.
In a liquid process, addition of a stirrer will help to eliminate thermal lag.
Since the thermocouple is basically a point measuring device, placing more
than one thermocouple in parallel can provide an average temperature
readout and produce better results in most air heated processes.
Proper sensor type is also a very important factor to obtain precise
measurements. The sensor must have the correct temperature range to
meet the process requirements. In special processes the sensor might need
to have different requirements such as leak-proof, anti-vibration, antiseptic,
etc.
Standard sensor limits of error are 4 F ( 2 C) or 0.75% of sensed
temperature (half that for special) plus drift caused by improper protection or
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