Sensor & Control Assy Development and Build

[TerryJC]

I had it in my mind to cut the current Ethernet link between the Reception router and the Railway Room in order to take it through the Hanham patch panel / switch, do I need to do that? Is there enough capacity in the Railway Room switch to allow us to connect the Hanham switch directly to it, If so is that desirable? It would mean that the Hanham box can be bought on line without disturbing the integrity of the rest of the network.

Penri,

The traffic at this point in the system today is minimal and consists only of Google interrogating its servers when people with Android devices connect to the WiFi. Currently the data throughput when we download the results once a week or so doesn't get that far. When the Lady Hanham SAC is connected, this traffic won't change, but obviously the Lady Hanham SAC Pi will now be sending data to and from SumpPi and the weekly downloads would include that data in the Lady Hanham Results and Logs.

Looking forward, the NAS Box will be connected to the Switch in the Railway Room Store so the traffic will change from SumpPi to that, but it won't make much difference apart from the addition of the Lady Hanham data. When the Zones are implemented the traffic is likely to reduce rather than increase.

With your original plan this would hardly change at all apart from the new traffic to and from the Lady Hanham SAC in both current and future scenarios. The switch in the Lady Hanham SAC Box would have to handle all the traffic to and from the Google servers, but that is tiny.

I'm not sure why you might want the third scenario. Obviously Google traffic would now bypass the Lady Hanham SAC Box, but that wouldn't save much and your original plan has the virtue of reducing the amount of cable needed.

Since the device in the Lady Hanham SAC is a Switch and not an Ethernet Hub, (as are all the like devices currently installed), the traffic between the WiFi Antenna and the Google servers will never make it to the Lady Hanham SAC Pi.

As far as the Railway Room Switch is concerned, the traffic increase with your original plan is minimal

So in essence your original plan is as good, if not better than any other.

[TerryJC]

I think I'll double up anyway because your point about testing the valve dry is a good one. I would have thought that there will be some headroom, but we can't rely on that because most users (in ponds, fountains, etc) would probably use mains-type wire rather than equipment wire, so the manufacturer would assume very little volt-drop.

OK. With the red and yellow wires paired together and connected to +12 V (Terminal Block Pin 5) and the blue and black wires paired together and connected to the MOSFET switched output (Terminal Block Pin 7), the volt-drop halves as expected to less than 0.5 V at my 16 Ohm Load. (BTW, the cable on the inside of the Box is different and the blue wire is green ).

I need to complete the Box wiring and finish testing the completed assembly and then I'll be ready to bring it back to WMT for ultimate installation.

[Penri]

I'll have to talk to my purchasing alter ego about achieving more consistency in procurement!

[TerryJC]

I have now completed final assembly and testing of the Lady Hanham SAC with the electronics installed into the IP65 Box. This testing encompassed peer to peer communication and functional testing of the three probe inputs, the three Float Switch inputs and the Solenoid Valve output all via the cables.

There is just one thing that came to light. The Ethernet Patch Panel and Ethernet Switch sit rather high in the box so that when the drop cables are added, the door has to be forced shut. I suspect that this puts undue strain on the Cat 5 connectors, but this shouldn't be a major problem providing that the door is not opened and closed too often.

I will drop the box off at WMT early next week. We'll need to discuss Setting to Work separately.

[Penri]

Hello

Finally labelled up the connector end of the Lady Hanham SAC box.

Not the prettiest job but ...

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