Thermo Scientific Thermo Scientific 3906, Operating Manual

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Thermo Scientific Model 3900 Series | 5-3
Product Description |
Chapter 5
In case the “light protection” feature is installed, the user can check the lamp function by
a supplied additional reflector.
4-20 Milliamp Output
The environmental chamber is equipped with 4-20mA output for the remote transmission
of temperature, humidity and CO
2
data. A terminal strip is located on the back of the
environmental chamber for convenience. Refer to Figure 5-4 for terminal pin
identification.
Figure 5-4
Terminal Pin Identification
Remote Alarm Contacts
Remote alarm connections are also included on the terminal strip providing Normally
Open (N.O.) and Normally Closed (N.C.) contacts. C is the Common terminal. The remote
alarm will activate when either the chamber’s temperature, humidity, or CO
2
go out of the
set alarm limits.
When opening the environmental chamber with light modules in operation do not
look directly in the light, wear corresponding safety goggles.
NOTE
Watch samples only temporarily with the light on.
NOTE
Since the lights emit the complete spectrum of daylight, this is not a UV source
(UV generator).
Temperature
4-20mA
(-20 to 80°C) Humidity
4-20mA
(0 to 100%)
Remote Alarm
30V 1A max.
CO
2
4-20mA
(0 to 20%)
NOTE
When the chamber temperature control setpoint is changed, the undertemp
safety thermostat must be reset to accommodate the change.
NOTE
The undertemp control is not directly calibrated. The numbers on the dial are
for reference only.