Tank use.

I have three feed tanks which are being filled from a choice of six bulk tanks.Any feed tank can connect to any bulk tank.If I have an input each for the feed tanks to represent their use and an input each for the bulk tanks to represent their use,what is the best way of programming the plc to enable a system to recognise which feed tank is connected to which bulk tank?

Regards Pauly

Best Way? Hmmm.....

First question; are the bulk tanks hard-connected to the feed tanks by some sort of valve grouping or does one manually connect each bulk tank to the desired feed tank?

Steve

The tanks are manually connected up.

Regards Pauly

This is only one man's opinion, but it seems to you might put in six 4-position selector switches, one position for each feed tank and one for "not in use". These switches would be located at the outlet of each of the bulk tanks. The guy who connects up the tanks would be responsible for making sure each switch was in the proper position when the connections are made.

I know this is a really simple solution and requires user intervention, but I have never run across any automatic system for this myself. At least not one that has manual connections being made.

Maybe someone else has heard of something better?

Steve

If by 'manually connected up' you mean that a supply hose from the bulk tank is connected up by hand to a nozzle for the feed tank then, at the connection point at each feed tank place a female plug with three pins from three inputs and a hot. Attached to the nozzle from each bulk tank attach a male jumper plug with permanent connection from the 'hot' pin to the appropriate input pins to form a binary coding (1-6) of the bulk tank. This could then be read by the PLC. If it isn't hooked up then the PLC shows 'no' bulk tank attached.

We have 5 silos conected to an outlet via a swing bend so where ever the bend is it makes 1 proxi switch thus selecting which silo to use so all we end up with is 1 proxi for each silo and if no proxi is made no silo is conected so it disables the outlet valve..

Jezz

Hi there,

I you would like to have an answer I need som more information. I've uatomated several tankfarms and I used sometimes hoses and sometimes the tanks were connected via collectors with automatic valves. There is also a way which Jezz describes, with swing bend.
The info I need to get from you
1 Is there a contamination problem?
2 Are you using hoses or a collector or a swing bend?
3 what kind of PLC are you using?

like to hear from you

Tank usage


Thanks for all the replies gentlemen,your help is very much appreciated I think each each of the ideas has potential.Fritz, I am using Klockner Moeller Easy relays, one at the tank farm looking after the bulk tank levels, one at the hose connection station checking which hose goes where and one at the feed tanks controlling the automatic filling.These will be networked together using the controllers' "Easy net "function.
Pauly

Connecting 3 Tanks 6 Ways . . .

pauly,

If am understanding you correctly, you already have physical relay inputs that tell you which Feed Tank is connected, and inputs that tell you which Bulk Tank is connected. The simplest and easiest thing to implement in your PLC is just 18 internal relays. For each of the 3 Feed Tanks, you will have 6 relay outputs. For example Relay 1 = "Feed Tank 1 Connected to Bulk Tank 1". Relay 1 is programmed to be on when Feed Tank 1 input is on and Bulk Tank 1 input is on. Relay 2 = "Feed Tank 1 Connected to Bulk Tank 2", and so on. Your last Relay 18 would be "Feed Tank 3 Connected to Bulk Tank 6".