E-stop!

[bad coffee]

Is there any way to program a permanent E-Stop in the BCS?

Looking around, the only way I see is to add it to every state in every process.
If Din8 is on then goto process 7 (all off.)

Not that I don't mind programming it for every step/process, but it seems there should be an easier way.

Ideally I'd like to select which outputs would turn off. I bought the 462 so I'd have extra temp inputs and could control my kegerator and my fermenatrix chamber with the BCS.

My brewing setup is going to be in a remote box, and I want the E-stop to only kill the outputs for the SSR's in the remote box.

Option B would be to wire in relays on each Dout line from the BCS that's in the control box. Basically an SSR controlling an SSR, which seems kinda clunky.

Is there any way to get an "E-stop" setting in the next firmware upgrade?

Cheers,
B

[JonW]

What version of firmware are you using? On mine, there is a "All Stop" red button near the top left of the screen (right above the process list).

[bad coffee]

I have the all stop, but I'm looking for a mechanical button on my control box that will be in the kitchen. I'll most likely be using my iphone and brewbuddy. But by the time I get to my phone, unlock it from sleep, and hit the 'All Stop" something could have gone seriously wrong, like a burned element or a very shocked brewer.

The more I think about it (or maybe drank enough coffee,) having an Estop kill all the outs would be fine. If I'm hitting the big red button, there's a reason. I can take the 2 minutes to reset the kegerator and keezer processes.

B

[JonW]

You could use a darlington transistor array like a ULN2803 on the outputs. A single chip gives you 8 channels. Your e-stop would just break the feed circuit to the chip and break all 8 circuits. Think of it like 8 miniature relays in a single chip. I can try to dig you up a reference schematic if you need.

[ECC]

I'm a big fan of estops killing power to everything. You want to really try to minimize the number of failure points between the button and the power. Like in your example, you have phone->wifi->router->network->bcs->ssr->wiring->element, any one of which technically could have been the 'failure' that caused bad things to happen in the first place.

The "All Stop" in the web interface is more of a convenience, I took care not to call it "Emergency Stop". If you want to do it right, find a mechanical button (or switch/contactor) that is rated high enough such that you can run the power source though it before it feeds the relays. That way there is only one failure point, the switch itself.

[bad coffee]

I'm going to have two 15-20A circuits in the box. Buying an estop that can handle 2x20A@110 isn't going to be cheap. If it won't work any other way, I might just put two GFI trip buttons in the box.

Can the "All Stop" button be called by a Din somehow?

B

[ohio-ed]

I'm going to have two 15-20A circuits in the box. Buying an estop that can handle 2x20A@110 isn't going to be cheap. If it won't work any other way, I might just put two GFI trip buttons in the box.

Can the "All Stop" button be called by a Din somehow?

B

I agree with ECC about needing a true E-Stop to be a very simple circuit that is fail safe.
In my opinion, any stop that relies on the BCS to shut down power is more for convenience thank an emergency.
You can wire an e-stop circuit with a mechanical relay that handles the current.

[missing_link]

One thing to keep in mind is that when an SSR fails, it fails in the on state. In my case I was using 25 Amp SSR's to power 1500 Watt elements. My pump lost prime and the element burnt out, this caused the SSR to fail but I didn't realize it. I swapped out the element and before I could get the pumps turned on, the element cooked again even though the BCS was still powering on. It took me a while to figure out what was happening. An E-stop on the 125v line would stop this from happening if you were to catch a stuck sparge before the element burnt out.

Linc

[clearwaterbrewer]

I would prefer to have the E-Stop stop all High voltage leaving the box, but allow a couple non-e-stop circuits inside, specifically for the BCS power, wireless adapter, and for my 12v flashing strobe.

Any issues with this? it has been 15 years since I worked on this stuff at caterpillar, but seem to remember there being stuff that was not on the E-Stop circuit...

-mike

[missing_link]

I bought a red mushroom switch on e-bay for $4.99 It can handle 20 amps. You can wire it normally closed or normally open. When you press it, it locks in position. To release it you have to twist. I'm going to get another and use this as an emergency stop on the heating elements.

Linc