BACKGROUND
AN outdoor Unitron CS21 controller regulates a grinder pump.
A liberty grinder pump, 230V 15.6A is not pumping. The sales website indicates the pump requires a control panel wit external capacitor P/N K001316 for retrofit.
The outdoor Unitron CS21 controller fell off its wooden post. The controller is now disconnected from the pump and cleaned up for bench testing and requirements evaluation. The pump has not been tested (yet) as I ordered new capacitors today.
Unitron Controller circuit diagram:
I am trying to determine the controller system requirements so that I can test each requirement in the controller or if necessary acquire a new controller that meets requirements. It is not enough to have a technical requirement: I feel it is necessary to understand why the spec is there.
Unitron Controller Photos: https://photos.app.goo.gl/JWp1YQGTieevw7DJ8
RESEARCH: Controller / System Requirements
Based on my reading of sales literature:
A Simplex Control Panel gives you many options that you cannot achieve on a direct wire installation. The first and probably most important is it puts your high water alarm and submersible pump on separate circuits. This means if the submersible pump fails and blows the breaker, your high water alarm is still functional. Secondly, our simplex panels allow you to use multiple floats to operate the submersible pump. The panel is designed to have an “OFF” float and an “ON” float for the pump. This gives you a lot more flexibility in setting your pumping range. The next big advantage of a simplex panel is it gives you the option to manually bypass the floats and test the pump. This makes for easy troubleshooting, and also the ability to manually kick the pump on if ever necessary.
From this paragraph the controller functional requirements:
- Alarm must work, even if the pump short circuits / blows a fuse
- A test mode to allow the user to directly command the pump to turn on
- At least two different sensors inputs (float switch) to command the pump on and command the pump off.
- Presumably: A third float switch input for alarm.
The technical requirement to have the alarm circuit separate from the pump-control circuit, follows naturally from said enumerated functional requirements.
The existing controller included 2 capacitors: presumably a start and a run capacitor. Capacitor photos are provided in a previous posting. The capacitors in the photo are labeled:
- 50 microfarads at 370VA
- 200-240 micro farads at 220VAC
An additional system requirements would include:
- Capacitors as required / specified by pump spec.
Ideally, after learning functional and technical requirements, I could test and troubleshoot the system. It would be nice to avoid an unnecessary expense.
If for some reason, it is necessary to replace the controller, this requirements identification exercise is necessary. A replacement controller must meet the system requirements. The sales website indicated: Below are Liberty control panels that can be used with this pump.
- SXHC24=3-3
- AE24HC=3-3
- IPS-24HC
- IPD-24HC
QUESTION
How can I systematically go about identifying the system requirements of the existing controller, so that the current controller can be tested and if necessary be replaced by a high quality cost-effective controller that meets system requirements?
