LIquid SAfety

Fill level monitoring in the lab: Easy, clear, handy

Solvent Monitor SM-411

The Solvent Monitor SM-411 is a 5-channel, WLAN-capable signal box with an interface for the communication with an HPLC system. The SM-411 is available in 3 application-specific versions:

Fill level monitoring in up to 4 solvent storages as well as 1 waste container.

Level monitoring in a central waste container, e.g. the Waste Solvent Net drainage system of HPLConsult GmbH, as well as in a small buffer vessel in which the continuously draining solvent is temporarily collected while the waste container is being emptied.

Level monitoring with 2 channels, e.g. water and acetonitrile, each for the automated refilling of a buffer vessel from a storage container.
No solvent is actively pumped, but the buffer vessel is temporarily pressurised with a slight vacuum during the refilling process. The SM-411p2 is working in combination with the VBU-2 (Vacuum Buffer Unit).

Display following the traffic light principle:

The traffic light principle fulfils the following principle for fill level monitoring: Simple but clear and practical. The filling status of each probe is indicated by an RG LED on the front panel of the SM-411. A yellow illuminated LED is indicating a forthcoming critical condition so that the adequate actions can be planned in advance but need not to be taken instantaneously but only when the corresponding alarm level is reached.

greenFill level is ok
yellowEluentsWarning level (e.g. < ¼ full) has been reached
WasteWarning level (e.g. > 3/4 full) has been reached
redEluentsMinimum level has been reached: audible alarm
WasteMaximum level has been reached: audible alarm

Thus, if a critical fill level has been reached, additionally an acoustic signal sounds.

LISA with remote inquiry via the Internet:

The LISA (LIquid SAfety) app allows you to check the fill levels of all SM-411 systems in your laboratory via the Internet. For each of your systems, the status of the eluents as well as the waste is displayed in tabular form with LEDs (green, yellow, red). With this app, you are informed about the status of the fill levels of your HPLC systems at any time at any place e.g. via your smartphone.



Up to 5 active or passive level sensors, e.g. 4 minimum level sensors (eluents) and 1 maximum level sensor (waste), can be connected to the SM-411.

The summarised signals "Eluent Warning" (yellow) and "Eluent Empty" (red) as well as "Waste Warning" (yellow) and "Waste Full" (red) can be configured and tapped via the DB9 interface as a potential-free contact closure in order that they and can be used as an input for the chromatography data system or any other switching module.

All signal inputs and outputs can be configured as a normally open (NO) or a normally closed (NC) contact closure so that the system may operate according to the "fail safe" principle (i.e. the alarm is signalled if there is an interruption or defect). The audible alarm can be activated or deactivated.

Documents: PDF-DokumentProspSM411e


Parallel evaporation with the


blowdown evaporator:

  • Interchangeable inserts for any rack format
  • Automated nitrogen control
  • fraction size up to 80ml
  • Partial evaporation possible