Flood Detection Siemens LOGO

[stickman1019]

Hi Lads,

I want to implement a flood prevention system with my domestic water pump.
The intention is to have the water pump cut off on a daily basis if the electricity consumption exceeds 3 kWh per day.

In terms of hardware I have a Siemens LOGO 6ED1 053-1FA00-0BA0 micro PLC with a Sifam Tinsley AP25-1DO kWHr meter.
12 x AC Inputs & 4 x AC Outputs

The kWHr meter has a pulsed output which shall be 1 pulse per kWHr and is configurable to have a pulse width of either 200/100/60 ms.

As this is DC and my inputs on the PLC are AC my intention is to use the pulse to activate a interposing Solid state relay which a contact will energise input I3 of the PLC.



I have never used a pulsed signal before if I configure it for the max 200 m/s will this be long enough for the LOGO plc to see the input ?



Attached is a copy of the program which seems to be working in the simulator OK just need procure a programming cable to do a physical download to the PLC

I appreciate this is small chips in terms of the general the usual queries on the site but any help is greatly appreciated.


Summary of the program below
Bypass Switch is to allow bypass of system in the event Im using a lot of water i.e power housing etc.
Float Switch is located at the pump location should a flood occur locally in the bunded area it will drop the pump.
Pulse Inputis the input from the kWHr meter
Weekly Timer this activates on a daily basis at midnight with a delay on energisation relay in series before it resets the counter for the next day.

 

[I_Automation]

I have used the LOGO in the past and can't guarantee it, but I think a 200ms pulse will be seen. I worked on a project where a cylinder switch triggered the cylinder to retract and that couldn't have been on near 200ms.



If you want to, get a DC timer set for OneShot and have that timer give a 1 second pulse

 

[stickman1019]

Thanks for the reply I just did a bit of rooting in the garage and found a brodersen unic xm which has a DC coil will bench test this and report back

 

[Zimmer]

Hi Lads,

In terms of hardware I have a Siemens LOGO 6ED1 053-1FA00-0BA0 micro PLC .....
12 x AC Inputs & 4 x AC Outputs

Doesn't affect your intention, but I believe that model has 8 relay outputs and doesn't matter if it's ac or dc either.

Just thinking out loud, but if your flood protection is purely based on kw hours used,

and I'm guessing the pump will use approx the same kw while it pumps, could you just not use a timer instead of the kw hr meter.

eg: say pump runs at 500 watt when pumping, then switch off pump, when it has ran for more than 6 hours total in the day, timer resets at midnight ??

.

 

[durallymax]

Can't find a datasheet for that specific model, a slightly newer version of that LOGO calls out 50ms for AC inputs so 200ms should be plenty.

 

[stickman1019]

Thanks lads reason I am using the kWHr meter is because I have one allready and should give an accurate idea on usage. I have decided to upgrade tot he 0BA8 model on the below link think for sake of 150 is will work better with the kWHr meter.

https://www.ebay.ie/itm/27612312886...hhvs8WoTGWOIw3VMgl05SQpdrqik3ST8aAh2WEALw_wcB

 

[stickman1019]

Well lads I decided to go ahead using the existing PLC I had and got communications up ad running with the help of a USB cable from Amazon.



Only issue I have is the LOGO PLC has no system clock.


So the section of my code that uses a Weekly Timer to reset the pulse count does not work.



I guess I need to build a daily timer using the LOGO logic. I am struggling with this as the 0BA0 has no internal flags.


Could anyone lend a hand as how to construct a daily timer using the functions available for the 0BA0

 

[stickman1019]

https://imgur.com/a/BQelzI8

https://imgur.com/a/oIPNHZc