Highgravity's new Single Vessel controller, EBC SV

First, let me add the disclaimer. I'm not affiliated with Highgravity in any way other than being a customer.

I'm in the middle of a full electric build and didn't want to build the controller. I contacted Dave at highgravity and discussed my plans and I decided on an EBC II controller with Ranco temp controller. This was two different devices and I was really wanting a single controller. I called Dave and ask about customizing his EBC III and he was going to do that for me. However, after thinking about it, Dave told me I wasn't the only customer asking for a single vessel controller. So, I have on the way, his very first EBC SV controller. Made with one PID and a very nice unit. Just what I was looking for and I'm sure many of you eBIAB'ers are looking for as well.

Here is the link for more information: HighGravity's EBC SV




Jim

Ragtop232 said:

First, let me add the disclaimer. I'm not affiliated with Highgravity in any way other than being a customer.

I'm in the middle of a full electric build and didn't want to build the controller. I contacted Dave at highgravity and discussed my plans and I decided on an EBC II controller with Ranco temp controller. This was two different devices and I was really wanting a single controller. I called Dave and ask about customizing his EBC III and he was going to do that for me. However, after thinking about it, Dave told me I wasn't the only customer asking for a single vessel controller. So, I have on the way, his very first EBC SV controller. Made with one PID and a very nice unit. Just what I was looking for and I'm sure many of you eBIAB'ers are looking for as well.

Jim

Click to expand...

I, too, am interested in something like this. I've purchased an enclosure, but it's not too late to return it. I'm not sure I'm up to the challenge of building my own controller.

I have a few questions about the product, though. Perhaps, I should e-mail Dave.

1. Regarding his system, I notice no valve on the pump. Of course, there is the ball valve on the kettle. I've read - at least for the Chugger pump - that you must control flow using a valve placed AFTER the pump, not before. Please correct me if I'm wrong.

2. The controller appears to have both a PID and a PWM. No problem with that. The controllers that folks have discussed that use both have a switch to determine which of these is controlling the SSR and, hence, the element. I don't see such a switch.

3. It appears that the brewer is using both PID and PWM at the same time. Wouldn't this confuse the SSR? Or is this not a PWM.

4. My understanding is the, although the control output of a PID and a PWM aren't exactly the same, both control the SSR by regulating the percentage of a cycle that the switch is on.

5. The only way I can understand how a PID and PWM can work together at the same time is if the PID is in "Manual Mode" and set at 100% so that the PWM is used to control the % of time that the element is on.

At least, in the video, the device works. I admit that I'm over-thinking this. I'm just trying to understand how it works.

Thanks,
Keith

The bird... Can't get past the bird. LOL

Having the pwm knob is nice, but I just don't see the need. Is it that hard to hit the "set" buttom once to engage manual mode and then just use the PID in manual mode when you are ready to boil?

If I were using a controller like this I would order a extra temp probe and place it at the output of my wort chiller (plate or cfc) By doing so you could use the PID as a digital thermostat. That way you could get your exact temp before pitching your yeast.

I'm very interested. I have a stand-alone electric HLT - and plan to keep mashing in a plastic cooler - so I'm really only interested in a boil kettle, and a controller to power said kettle.

I just have to weigh out whether this particular unit is overkill for what I'm going to use it for...... after all, a boil-only controller doesn't really need a PID in the first place, it only needs to know one temperature - 210*F.

I was itching to buy a pre-built eKettle ... But if I piece together my own boil kettle using a cheap 60qt restaurant stock pot, and the DIY guides on here for the 5500w element installation.... maybe I can do the kettle for under $200, it might justify the cost of this controller...

Which reminds me that I gotta find a couple of grand for electric work before I can do any of this. Stupid old house having a small electric panel. Probably will need a new main panel, a service drop upgrade, and then two new dedicated runs & outlets for the eBrewery before I can begin.

Ragtop232 said:

...I'm planning on taking the PID to manual for boiling and adjusting the boil rate with the PWM.

Click to expand...

Jim,

I'm trying to understand this last part. If the PID is in manual, then you can adjust the percentage of on cycle. If it's an Auber PID, manual mode starts at 0%, then you use the up arrow to get to where you want to be. It takes a couple of seconds to get to 100%. Are you saying you would put the PID in 100% then use the PWM to dial in the amount of power you want? It sounds redundant to me.

I'm probably not reading this right.

I think I'm understanding how this device works. I was envisioning two cycling switches connected in series and was having a problem with that. I'm thinking that the ONLY way this device would function is for the PID to always be at 100%.

I was thinking that the PID pulsated like the PWM. I believe that it does, but only when in manual mode and when set at a level less than 100%. Forgetting about the PWM for a moment, when you set the PID to strike water temp, the PID is on 100% of the time until it reaches temp. When the mash cools below the temp, it comes back on at 100% to get the temp back up. I've read about "autotuning" the PID, so I don't know if the PID does something different as it approaches the set temp.

This might explain how, in the video, he shows that you can even control the amount of heat with the knob while you're heating up the water. IOW, you might not want to use 100% power to bring the temp up (to do it more gently). If you set the temp on the PID, it will want to run at 100% automatically during this ramp up time. So, you can still use the PWM.

The only time the PID cycles quickly on/off like a PWM is when you put it in "Manual" mode and set it to something less than 100%. If you set the PID manual mode to anything less than 100%, I don't think it will work well.

So, when you get ready to boil, I guess you turn the PID to "Manual" mode at 100% (so it'll stay on), then use the PWM dial to control the pulsating.

I'm thinking that the system will get confused if you set the PID for something less than 100% while you're trying to control with the PWM. The cycle times (frequencies) for the PID in manual mode and the PWM might be different, and the SSR will only be ON when BOTH the PID and PWM are in their respective "ON" phases.

I was adding up the costs of components to build my single vessel control panel and was coming very close to the cost of this device. Therefore, I might explore the possibility to get one of these instead of building a control.

Thanks,
Keith

That "might" answer my question. My understanding from the "PWM Show Us How" thread is that a PWM - pulse width modulator - does cycle. It has nothing to do with controlling the "amount" of current or wattage going to the element. IOW, it's NOT the same thing as a volume control.

So, this knob must not be a PWM. I admit here that I might be incorrect. I think I'm going to e-mail Dave along with a link to this discussion to see if he can shed some light on it.

A PWM varies the amount of "heat" (nothing to do with wattage, volts, amperes) an element puts out only by varying the percentage of time the element is fully on vs fully off. IIRC, most cheap PWMs are never fully off or on, but might range from 5- 95%. Moreover, if I'm understanding the PID correctly, it does the same thing when in "manual" mode at something less than 100% as a PWM.

It's unfortunate that the electricity experts are not weighing in on this.

Respectfully,
Keith

Caution: This might sound harsh. I am not questioning your decision, or those of the makers of the High Gravity EBC SV. I'm just trying to understand the logic of the system. My comments are not intended to cause undue stress or strain. If you ask me to remove my comments, I will.

Using a PWM for the Boil will be fine. I'm was just trying to figure out if the setup of the controller. At 4:20 in the video he changes the temp for the mash out using the buttons on the front of the PID. If the PID is in manual mode, changing the percentage of power is just as easy. At 4:35 he states, "When mashing..." that it's a good idea to leave the power in the mid range so it won't overshoot the mash temp so much. This is odd because the PID won't overshoot the temp if it's tuned for the system.

From the video at about 4:45, it appears the PWM is after the PID. He states at 4:47 "for mash out you might want to go ahead and max out the power so it raises the temperature faster". Here's why I find this odd. The PID provides the control circuit to the SSR. The PWM also controls the SSR. If you have two inline devices providing control input to the SSR, what's the real amount of time the SSR is off/on? The PID should be autotuned to the system. If it is, then it won't overshoot the temps. At what percentage of the PWM do you set that? 50%, 75%? But when you add the PMW and it is set to anything less than 100%, less than 100% of the control signal from the PID is going to make it to the SSR.

It doesn't make sense to me to limit the output control circuit of the PID with the PWM.

That's all I have to say. No offense to you or High Gravity.

Paul

stlbeer said:

I'm just trying to understand the logic of the system.

Click to expand...

Paul,

Your question/comment does a little better job of articulating my main question. In message #11, I "think" I explained how it might work. As you suggest, and I said, the main use of the PWM comes into play only when the PID is running at 100% - such as during ramp up or manual mode.

I think the way it's used during boil is that the PID is set to Manual Mode at 100% and the PWM is used to control the boil as opposed to pressing the up/down buttons on the PID.

If someone tries to set the PID at anything less than 100% when adjusting the PWM, the SSR will not get the correct switching signals, and the system will stutter.

I think High Gravity should simply include a selector switch on the front: PID/PWM. That would take all the confusion out.

I sent an e-mail to Dave at High Gravity with the question.

Respectfully,
Keith

Ragtop232 said:

Keith, the PWM/control knob on this device does not cycle the element. The element will be on 100% of the time, but the PWM will vary the wattage to the element. Think of it like a dimmer switch on a light bulb.

Click to expand...

This is incorrect. A PWM controls the percentage of the frequency the control circuit is off/on. The off or on is 100%. At 50% the control circuit is on 100% for half the time and off 100% for the other half of the time. Most PWM's use very short frequencies so it appears the device is running on lower power.

Actually, now that I think about it, the PWM is actually going to be detrimental. The PID has an auto-tune mode wherein it actually cycles several times and learns how fast your system heats up and cools off in order to anticipate how fast/how much/how long to apply power to keep the temp constant. This is how we set up our PID parameters.

Now......that happens if you set your system up and the PID "learns" it's setting with the PWM cranked to 100% cycle BUT then on brew day you decide to turn the PWM down to 50% cycle? Now the algorithm that the PID uses is not going to be correct because even though it is cycling the element as it did when the PWM was at 100%, only half of that power cycle is going to be applied to the liquid and the temp will not increase as fast as the PID expects it to. The results are going to be that the PID won't be able to maintain temp properly unless you run the whole "auto-tune" process again with the PWM set at 50% cycle.

Hi Guys,

This is Dave, the guy in the video.

We take a different approach than most people when we build brewery controllers. This is because we started several years back with manual control, and developed our own analog power modulation circuit. We like it so much, that we have continued to include it in all of the next generation controllers. We do not use an SSR at all. We use two mechanical relays, and switch both hot wires so that when it's off, it's off. The PID is operating in the simple thermostat mode, and the power level is modulated with the TRIAC based circuit. We modulate the pulse width of each half-cycle of the line power.

While some might say, Why use a PID in simple thermostat mode, when you can pulse an SSR and let it Autotune?" We say, "Why would you want to control a boiling kettle with up/down buttons?

Cheers,
Dave Knott

High Gravity
7142 S Memorial Dr
Tulsa, OK 74133
(918) 461-2605

Todd and I were just discussing this. I'm glad he posted his concern to the forum. I had wondered if the PID might start cycling/pulsating the current to the element as it reached the set temp.

Having a PID and a PWM wired in series (or in-line) is analagous to a pair of 3-way switches connected to a light bulb. If you have 2 kids operating these 3-way switches such that 1 switch stays on and the other is flipping on/off - e.g. 1 sec on 1 sec off for 50% of a 2 sec frequency - then the light will be on 50% of the time. If they are both flipping their switches at exactly the same frequency and for the same portion of each cycle, the light will either be ON all the time or OFF all the time depending on where they start their flipping. Really confusing is if they're flipping their respective switches at completely different frequencies and at different pulse-widths. There will be a stuttering ON signal sent to the SSR. I'm thinking that the control signal going to the SSR would resemble a Morse code message - only very rapid. Might this cause undue stress on the SSR and premature failure of the SSR?

So, I reiterate, that the only logical way for this to function appropriately - unless I'm not understanding the logic - is (1) for the PWM to be at 100% (if it's possible) during ramp up and mash and (2) for the PID to be in Manual Mode at 100% if you want to control the temps with the PWM.

Ragtop, I wonder, since you and Dave are communicating, if they might be willing to add a DPDT selector switch to this controller (PID/PWM) in order to make it more functional? One can select PID during the heating of the strike water and during the mash. Then, you flip the switch to PWM to get to and maintain the boil.

Respectfully,
Keith

DaveKnott said:

Hi Guys,

This is Dave, the guy in the video.

Click to expand...

Dave,
Thanks for weighing in on this. I'm sure that there will be other question, so please stay tuned. You might find a great market here for the EBC-SV.

One quick question: my understanding of why folks use SSRs instead of mechanical relays is that the mechanical ones would wear out at the pulse frequencies used by PIDs and PWMs. I don't guess this has been a problem in your controllers since you've been doing this for a good while.

I'm sure that I could build a controller, but I'm not sure I want to put myself thru the challenge with everything else I have on my plate right now. I'm trying to build up a comfort level with this controller (your product) using information I've gleaned from studying various e-build postings on this Forum.

Thanks,
Keith

OK, I was completely wrong in how this works. I was thinking the PWM or varying the wattage via the analog knob is what was being referred to as the PWM. I'm sorry for the mis-information and wrong answers. I think Dave has answered the questions in his above reply.

I will delete my posts so as not to confuse anyone looking at this thread for answers as to how it works.

Jim

Dave,

Thanks for the answers! I'm not aware of a simple thermostat mode for a PID. It looks like you use Auber PID's and so do I, but I've been through the manuals and can't find a simple thermostat mode for it. How is this accomplished?

And honestly, you push 1 button to get into manual mode then push another to set the percentage. It's almost exactly the same as changing the temp for mash out, but I understand your logic now.

Appreciate the explanation too Dave, I guess the only question that I have is why install that nice multi-functional SYL-23xx PID when you're simply going to use it as a "dumb" t-stat? Why not use a base model PID like the SYL-1512A so that all the additional features (PID, manual mode, alarms, etc) aren't going to waste?

We like the SYL-23XX series controller because it displays the set point and the measured value simultaneously.

Setting the parameter At=0 puts the controller in thermostat mode.

Since the thermal mass of a hot liquor tank is fairly large, once the temp has reached the set point, the heating element spends most of the time in the off state. There is really no need to use any fuzzy logic here. Simple thermostat mode will maintain the temperature very well. But people can still play with the Autotune parameters here if they want to. You would just want to have your cycle time (t) set to 20.

There are many ways to put together a brewing system that does the job very well. Since we are designing controllers for people that didn't build their own, we wanted the operation to be simple and straightforward for everybody. Twisting a power knob is something that everyone understands.

Understood, thanks for the reply.