Controller (Digital Plus) - Thermo Scientific NESLAB EX Series Installation, Operation And Maintanance Manual

Controller
(Digital Plus)
Alarm. If the alarm sounds, use this button to toggle the alarm off and on. If
the cause of the alarm is cleared but then reoccurs, the alarm will sound again.
Mute
The button is also used to abort changes to the setpoint and temperature
alarms. It is also used to abort changes when configuring the unit for external
probe, serial communication, timer operation, or offset mode.
NOTE: Pressing and holding any of the following buttons for five seconds takes
you to their calibration or setup loop.
External Probe. Pressing the Sensor button displays the external probe
temperature and lights the LED indicating that the bath is monitoring and
controlling to this temperature. The unit will continue to monitor the internal
Sensor
bath temperature to ensure the bath is running in a safe operating mode.
NOTE: If there is no sensor attached (or the circuit is open), or serial communi-
cations is enabled, the button will flash, and the alarm will beep three times.
The display will momentarily show an error message and then return to the
reservoir fluid temperature.
NOTE: The temperature display may drift for up to 10-15 seconds when
transitioning between temperature sensors. This is normal operation.
Serial Communication. Pressing Computer enables/disables the serial
communications mode of operation. In this mode all changes to the setpoint,
alarm limits, etc. must now be sent by a remote device using RS-232 or
Computer
RS-485 protocols. You can still view all settings locally but cannot alter them.
Once enabled, the Computer LED will flash when sending and receiving
signals. See Appendix B for additional information.
You can also turn the unit off by pressing but the unit will remain in the
serial communication mode. To restart, send another start command.
NOTE: If the unit is shut down in the serial communication mode and you need
to start the unit using the local controller, simultaneously depress and hold
both arrow keys for approximately 10 seconds. The display will then show the
internal probe temperature, and the alarm will sound. Press the LED
Computer
and turn off the LED and disable serial communications. Turn the controller off
using . You can now start and operate the unit with the keypad.
To setup for serial communication see Computer Setup Loop on page 24.
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