Switchos Switching Devices
SSV Control

Solvent Selection Valve (SSV) control for new systems

For new Switchos systems, which are controlled via the LC Packings Switchos II SSV device driver (see  Switchos Capillary/Nano HPLC Switching Device: Installation), use the following command to indicate the position:

1.000 SSV.Position= C

In this case, you do not need to take any switching into account.

 

Solvent Selection Valve (SSV) control for old systems

For old Switchos systems, which are controlled via the LC Packings UltiMate/Switchos device driver (see  Switchos Capillary/Nano HPLC Switching Device: Installation of Old Devices), you have to use relative command to control the solvent selector valve (SSV). In addition, the valve can be moved in one direction only:

Thus, it is not possible to switch the valve directly from position B to position A. You have to switch the valve to positions C and D first.

Switching a relay takes 1 second. That is why you have to consider the different switching times.

First, initialize the valve. During initialization, the valve always switches into position A. The first switching of the valve takes 2.0 seconds (= 0.0333… min). All other switching actions take 1 second plus an additional buffer time of 0.1 seconds; i.e., in the program, 1.1 seconds (= 0.018 min) are required for all switching actions but the first one.

For example, a program for switching the SSV as fast as possible into position D at the beginning of the program looks as follows:

0.000 SSV.On Duration=2.00 ; Initialization: switches to pos. A

0.035 SSV.On Duration=1.0 ; switches to position B

0.055 SSV.On Duration=1.0 ; switches to position C

0.075 SSV.On Duration=1.0 ; switches to position D

0.095 ...

The next command is allowed after 0.095 min at the earliest.

You can also create this program part automatically using the PGM Wizard. Use the following settings:

 Note:

The corresponding comments are automatically generated as well.

Troubleshooting

The following error message appears in the PGM Wizard if you do not consider the switching times of the solvent selection valve (SSV; i.e., actually of the relay):

You have to correct this error to continue with the next step of the PGM Wizard.