Relay Outputs - Thermo Scientific Corona Veo Operating Manual

11 • Appendix
Autozero
Divert

11.2.2 Relay Outputs

Pump Off
CC1 and CC2
Page 254
The Autozero input can be used to set the signal of a channel to a zero
point, regardless of the current that is being measured.
Allow sufficient time after you performed the autozero and before
injection to ensure that the autozero command is completed.
Alternatively, an autozero may be performed during a run. In this case,
make sure that autozero occurs at a point in the chromatogram where
the response curve is expected to be reasonably flat, that is, 15 seconds
prior to the elution of a peak.
The Divert input can be used to control the stream-switching valve with
a third-party driver.
To use output contact closures, connect the outputs according to theirs
+ or – polarity. Connect the third wire of the I/O cable to the ground
below the polarity of the output to which it belongs.
The Pump Off output contact is used to send a signal to the pump or
other external device to stop the flow of mobile phase and turn off the
pump. This signal may be used to turn off the pump to prevent the
detector from being flooded with mobile phase if the gas pressure falls
below 50% of the required gas volume for more than 60 seconds.
To use the Pump Off contact closure, the HPLC system must be able to
accept an input from the detector that can be programmed to turn off
liquid flow. In some cases, a special cable is required.
The CC1 and CC2 contact closures can be used to start an external
device, for example an autosampler, or can be used to change a valve
position. The two ports act in similar fashion to the Pump Off output.
TIP If you use the Chromeleon software, relay output CC1 corresponds
to the relay signal CAD_Relay_1 (default name), and relay output CC2
corresponds to the relay signal CAD_Relay_2 (default name). The Pump
Off relay output is not available in the Chromeleon software.
Charged Aerosol Detectors Corona Veo (RS) Operating Manual