How do I replace a bubbler system with the FOGRod?
Changing a bubbler system to the FOGRod is pretty simple. The important question – is the bubbler actually doing pump control as well as measuring level?
The LIT gives a level output (10 relays + analog output), but doesn’t do pump control.
If the bubbler is not doing pump control then it’s very easy – it is probably feeding an analog signal into something else (e.g. a pump controller, a PLC). Connect the analog of the LIT into the same place and you have replaced the bubbler.
One important point – if it’s an analog output, the range of the bubbler may be different from the range of the LIT. Our unit gives 1mA steps for each 6″ or 9″ (depending on the length of the FOGRod). Someone may have to change the setpoints in the PLC or pump controller. It’s the exact same issue when replacing a pressure transducer.
If the bubbler is doing pump control then you need to add something along with the LIT. Usually an alternating relay will be all you need – the additional cost is under $100 and there are lots to choose from. Anyone who has wired up or maintained lift station panels will be able to take care of this.
For completeness.. a note that the LIT can do basic pump control without alternation. You just use the auxiliary on the starter to hold in the run signal once the pump starts. For example, suppose contact 5 is your start point and contact 1 is your stop point. Relay 1 will break the circuit – i.e., stop the pumps. Relay 5 will start a pump – that is, be wired to one of the starters. The auxiliary from the starter will hold in the starter once the pump is running (and the level drops below contact 5).