Sheldon Shel Lab - Reference Sensor Devices

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INTRODUCTION
REFERENCE SENSOR DEVICES
Must be purchased separately
Reference sensor devices or a combined device are required for calibrating the
incubator temperature and CO
2
displays.
Reference devices must meet the following standards:
• Accurate to at least 0.1°C
• Accurate to at least 0.1% CO
2
The devices should be regularly calibrated, preferably by a third party.
Temperature Probes
For temperature, use a digital device with a wire thermocouple probe that can be
introduced into the incubation chamber through the unit access port. Select a
thermocouple suitable for the application temperature you will be calibrating at.
CO
2
Sampling
For best CO
2
accuracy, use a digital gas analyzer with sample tubing connecting to
the incubator CO
2
sample port. The barbed adapter gas fitting on the port connects
to 3/16-inch (4.76 mm) inner diameter (ID), 5/16-inch (7.94 mm) outside diameter
(OD) tubing.
Why Probes and Tubing?
Reference readings taken outside the chamber using wire temperature probes and
CO
2
sample tubing drawn through the sample port avoid chamber door openings.
Openings disrupt the chamber temperature and CO
2
concentration level. Each
disruption requires a minimum 1-hour wait to allow the atmosphere to re-stabilize
before continuing.
No Alcohol or Mercury Thermometers
Alcohol thermometers do not have sufficient accuracy to conduct accurate
temperature calibrations. Never place a mercury thermometer in the incubation
chamber. Always use thermocouple probes.
CO
2
Reference
Temperature
Reference