Integrating the New SumpPi Interface into the System

[TerryJC]

I think what you need is an open collector or open drain buffer, like the SN7407 or SN74LVC07A, they may need a pull up resistor to the "high" voltage Vcc, dependent on what they are driving.

Penri,

As I understand it, the open collector outputs in these devices will work with the SSRs without a pull-up, providing that they have a DC path through their inputs. Do you have one to hand so that we can check?

I have the PWM Motor Drive Board that you bought at the beginning of the project here and it has an input resistance (measured with a DMM) of 100 k. That should work without a pull-up when we get round to installing it.

[Penri]

Terry

I have an SSR here, of the same type we use for the WMT pumps. it needs a current of 7.5mA according to the spec. sheet. 5407 / 7407 as speed to at least 30mA.

I can bring it up to you after lunch and before 14:00 if that's ok. Would you also like the 5407?

Penri

[TerryJC]

Yes please, to both.

Not too soon though, we haven't started our lunch yet.

[TerryJC]

The software for the new SumpPi design and Hall Effect Probe has now been released and the hardware is being made ready for installation tomorrow.

At this time, it is not intended to deploy the new Gate Valve at the same time as the new SumpPi because that is felt to be too many changes at once. However, the newly released code will not work straight out of git because it includes support for the Gate Valve. To allow this deployment to be carried out, the following code has been commented out temporarily on the SumpPi SD Card only:

• main.py - Line 192: 'monitors.append'.
• config.py - Lines 158 to 163: Socket definition
• config.py - Lines 246 to 264: Gate Valve definition.
• coretools.py - Each entry of sockets[ "SOCK14"] in 9 places.

Removing these at a later date will allow the Gate Valve to be deployed.

[TerryJC]

Sitrep on Commissioning of the new SumpPi, which was started yesterday:

• Tthe new SumpPi Assembly was fitted into the IP65 box on site and the connections from the outside world screwed into the TB.
• ]The PoE injector was removed from the wiring and a new 12 V PSU installed inside the case.
• The PoE Splitter was removed from the old ButtsPi (now WButtsPi) and the unit fitted with a new 20 V PSU.
• The two encased units were tested on the bench with their Ethernet adaptor connected directly together. It was established that the Float Switch input and the SSR outputs were both behaving as expected.
• The two boxes were returned to their installed positions, the Ethernet cabling was connected and both units were switched on.

Two problems were encountered: first we couldn't establish communications with WButtsPi. It is believed that this was caused by the bad batch of Ethernet plugs that were used in the original assembly. By bypassing the suspect link proper comms was established.

The second problem is still outstanding. During normal operation, the Butts Pump seemed to be operating all the time, even when the Sump was nearly empty. The intention is to debug this tomorrow, with SumpPi connected to a monitor and keyboard. It is uncertain what is causing this because the Main and Butts Pumps both use the same piece of code to operate. However, I now recall that we had some problems with connecting up the wiring from the Float Switch, but there would also have to be a problem with the logic somewhere.

The new Hall Effect Probe seems to be working fine; see the attached Results File from the last run.

[TerryJC]

The new model SumpPi is now installed and running. The network issue was confirmed to be caused by poor connections and the anomalous behaviour of the Butts Pump was traced to an error on the Build Instructions so that the Butts Pump was being controlled as the main Pump and vice-versa.

The updated drawing may be found at viewtopic.php?f=15&t=113&start=10#p1773.

Attached are the latest set of readings.

[Penri]

Nice set of readings, everything looks ok so far.