Hello,
I have had a little bit of spare time and decided to do something with the odd bits and pieces that I had laying around.
The physical and logical layouts are quite messy, and I have left parts in that could be useful for other functions. I also still working on it when time allows.
I started with a single phase 550w pool pump and an intex sand filter with SWG unit attached. The following has been added, with the help of the Siemens Logo 8.3 unit and logic:
- VFD control of the pump motor.
- Currently keeping a constant pressure via PI controller to the VFD (just to get to grips with how it works).
- Heat pump control via contactor.
- Web access and control to the Logo.
- MODBUS monitoring.
- E-stop.
- Auto/manual modes.
- Schedules for the pump and heatpump.
- Running hour tracking of both the pump and heatpump.
In progress:
- Control of the Intex SWG. (Relay)
- Addition of a temperature probe. (Analogue Input)
- Control via MODBUS. (TCP)
- Pump dry-run protection. (Pressure Logic)
- Integration with electric billing to run the pump and heatpump at the cheapest slot each day. (Home Assistant automation and Flag in Logic)
- Fixing the heatpump. (Went on hold, heat exchanger needs hot plastic welding)
Learning curves:
- Running the VFD backwards causes the impeller to unscrew and jam. This was accidental and due to mis-wiring. Somehow this did not damage the ceramic seal.
- VFD fuse was too small so it popped.
- Using Loctite 577 on stainless steel or plastic requires SF 7649 activator otherwise it takes a long time to cure.
- Some Intex pumps that have PSC motors can be VFD controlled.
It works.
The pump was using 550w previously but now I can notch it down to 175w.
The VFD is an AT-1 from Amazon, which is supposed to be single phase in to three phase out. However, there is a setting which enables you to use it on single phase PSC motors after removing the capacitor. An analogue output from the Logo then connects to an input on the VFD.
I will collect photos and screenshots of the current mess, and add them to this thread.
Tony
I have had a little bit of spare time and decided to do something with the odd bits and pieces that I had laying around.
The physical and logical layouts are quite messy, and I have left parts in that could be useful for other functions. I also still working on it when time allows.
I started with a single phase 550w pool pump and an intex sand filter with SWG unit attached. The following has been added, with the help of the Siemens Logo 8.3 unit and logic:
- VFD control of the pump motor.
- Currently keeping a constant pressure via PI controller to the VFD (just to get to grips with how it works).
- Heat pump control via contactor.
- Web access and control to the Logo.
- MODBUS monitoring.
- E-stop.
- Auto/manual modes.
- Schedules for the pump and heatpump.
- Running hour tracking of both the pump and heatpump.
In progress:
- Control of the Intex SWG. (Relay)
- Addition of a temperature probe. (Analogue Input)
- Control via MODBUS. (TCP)
- Pump dry-run protection. (Pressure Logic)
- Integration with electric billing to run the pump and heatpump at the cheapest slot each day. (Home Assistant automation and Flag in Logic)
- Fixing the heatpump. (Went on hold, heat exchanger needs hot plastic welding)
Learning curves:
- Running the VFD backwards causes the impeller to unscrew and jam. This was accidental and due to mis-wiring. Somehow this did not damage the ceramic seal.
- VFD fuse was too small so it popped.
- Using Loctite 577 on stainless steel or plastic requires SF 7649 activator otherwise it takes a long time to cure.
- Some Intex pumps that have PSC motors can be VFD controlled.
It works.
The pump was using 550w previously but now I can notch it down to 175w.
The VFD is an AT-1 from Amazon, which is supposed to be single phase in to three phase out. However, there is a setting which enables you to use it on single phase PSC motors after removing the capacitor. An analogue output from the Logo then connects to an input on the VFD.
I will collect photos and screenshots of the current mess, and add them to this thread.
Tony
