Dedicated Herms Guide, Problems And Solution Thread

[Frag_Dog]

I am planning to put an order in to Auber Instruments for control of my HERMS. I just wanted to run the list past people experienced with building a HERMS to make sure there are no glaring omitions

PID Temperature Controller w/ Ramp/soak, Kiln (SSR Output) - $77.95
40 A SSR - $19.00
Heat Sink for Solid State Relay, 40A - $19.50
Liquid tight RTD sensor, 60 mm probe, 1/4 NPT Thread - $23.95

Have I got the right PID? Is there a PC interface cable I need to program the ramp/soak or is that done with the controls on the device? I realise I don't NEED a heat sink, but its only a few extra bucks and I may as well get it now... According to the specs the PID can use a RTD Sensor, and from what I read, these are better then the K types.

I'm going to get some sort of waterproof box to stick it all in. Then get it wired up by a proper sparky, but I'll worry about that once i get this squared away.

 

[hockadays]

looks pretty good. get the heat sink as better to have it rather then not. I would also avoid their SSR as I had one melt on me recently lucky I was there and caught it early and just lost the SSR. You program the pid through the pid itself pretty easy once you do it a few times.The RTD is better then the K type, I had the K type first then went the rtd for its accuracy. I have the same setup as this so if you have any more qs pm me ..

 

[Crusty]

Hi all,
Just curious to find out what the water temperature might be in your hex vessel if the wort is coming out & maintaining 66deg.
Would it be a fair assumption the hex water may be in the mid to high 70deg range or higher?

 

[cdbrown]

If it's just maintaining it then it would probably be ranging from 66-80. But mostly just sticking around 66. Ramping is a different beast and would be higher.

All depends on the temp going in really.

 

[Crusty]

If it's just maintaining it then it would probably be ranging from 66-80. But mostly just sticking around 66. Ramping is a different beast and would be higher.

All depends on the temp going in really.

Thanks cd.
Just curious to know as the centre of my outlet is approx 60mm from the top of my pot. Was a little concerned about how much water needed to cover the coil & if the water was reaching temps to start the water rolling I might get some spillage due to my hex water level. Do you lose much to evaporation over the course of a 60-90min re-circulation requiring some topup water to the hex pot. My hex pot is only 7.6lts.

 

[hsb]

I get no noticeable evap loss from HEX over 90 min mashes and no boiling. My water level sits only 1-2cm below the lid of HEX.
The PID should throttle the HEX so you get nowhere near to boiling, switching on/off more the closer you get to target temp.

Fraser John mentioned a few pages back about forgetting the HEX is on sometimes and it boiling that way...

 

[Crusty]

I get no noticeable evap loss from HEX over 90 min mashes and no boiling. My water level sits only 1-2cm below the lid of HEX.
The PID should throttle the HEX so you get nowhere near to boiling, switching on/off more the closer you get to target temp.

Fraser John mentioned a few pages back about forgetting the HEX is on sometimes and it boiling that way...

Great news. My water level in the hex will be around 30-40mm from the top of the hex pot allowing a comfortable level over the coil.
Gotta hurry up & get this thing operational.

 

[cdbrown]

I normally only top up the hex when setting up the rig as it splashes about when moving to/from the shed. I've got a 7.6L pot and the water level is just under under the inlet and outlet pipe. As there's plenty of copper in the hex it warms up pretty quickly.

The hex will boil away if the target temp isn't reached as the PID will continue to pump power to the element. Be mindful of a stuck mash as it can boil away if the liquid isn't moving past the temp gauge. I use the hex to ramp up to mash out temps and I can't remember it ever coming to the boil, you might get some air bubbles around the element as water just like any kettle, but it's only small amount.

 

[Crusty]

I normally only top up the hex when setting up the rig as it splashes about when moving to/from the shed. I've got a 7.6L pot and the water level is just under under the inlet and outlet pipe. As there's plenty of copper in the hex it warms up pretty quickly.

The hex will boil away if the target temp isn't reached as the PID will continue to pump power to the element. Be mindful of a stuck mash as it can boil away if the liquid isn't moving past the temp gauge. I use the hex to ramp up to mash out temps and I can't remember it ever coming to the boil, you might get some air bubbles around the element as water just like any kettle, but it's only small amount.

My initial strike water is over 3l/kg, 3.75l/kg most commonly. Hopefully stuck sparges won't be encountered with this ratio & a little throttling back with the ball valve.
Is your copper coil fully immersed or do you have the top of your coil exposed to the air? Not too sure if that's important or not.

 

[cdbrown]

The coil is fully immersed, the inlet and outlet pipes aren't. The inlet/outlet are only exposed to the air in the pot with the lid on which is warmer than the outside temp.
I am planning on insulating the silicone hose at some time to reduce any losses and reduce the load on the herms.

 

[mateostojic]

Gents,
I have been lurking around the herms threads for a while now and am currently building my own 4 vessel single tier e-herms. I have been working on the control box and have come up with an arrangement. It would be very helpful if you guys could have a quick look at it and make some suggestions for improvement, as I am sure there is room for improvement since I am a complete newbie when it comes to electrical wiring, but I have done my best to learn.

Before anyone makes the comment, I would like to mention that I am intending to get a qualified sparky to have a look at the control box before I start using it.

A bit about the design:
- 4 vessel E-herms designed for single batches, which is powered by a single 10A circuit.
- The HLT, MLT and HERMS heating elements are all 2200W
- There is a water pump as well as wort pump, both of which are 809 series March
- The thick wires in the diagram are 1.5mm2, the thin wires are 1mm2 and the purple wires are 0.5mm2
I have tried to use relays switches to make it so that only one heating element can be powered at any given time, so that I can use a single 10A circuit.
I have also put in an amp meter to make sure my system is not drawing too much power.

Thanks in advance,
Mate

View attachment Control_Box_Wiring_Rev_2a.pdf

 

[mxd]

seems fine to me (n.b s/w guy who releases smoke from most things he touches)

how big is the kettle etc..

how are u doing your power priority ?

 

[mateostojic]

All three vessels are 50L.
The relays are set so that the HEX element has priority, but when it is not on, the power is allowed to be used by the HLT element.

I should also mention that with the three PIDs; the first will be used to control the HLT element, the second will be used to control the HEX element (probe on outflow) while the third will just be used to monitor the wort out of the MLT.

Mate

 

[dmac80]

Gents,
I have been lurking around the herms threads for a while now and am currently building my own 4 vessel single tier e-herms. I have been working on the control box and have come up with an arrangement. It would be very helpful if you guys could have a quick look at it and make some suggestions for improvement, as I am sure there is room for improvement since I am a complete newbie when it comes to electrical wiring, but I have done my best to learn.

Before anyone makes the comment, I would like to mention that I am intending to get a qualified sparky to have a look at the control box before I start using it.

A bit about the design:
- 4 vessel E-herms designed for single batches, which is powered by a single 10A circuit.
- The HLT, MLT and HERMS heating elements are all 2200W
- There is a water pump as well as wort pump, both of which are 809 series March
- The thick wires in the diagram are 1.5mm2, the thin wires are 1mm2 and the purple wires are 0.5mm2
I have tried to use relays switches to make it so that only one heating element can be powered at any given time, so that I can use a single 10A circuit.
I have also put in an amp meter to make sure my system is not drawing too much power.

Thanks in advance,
Mate

Mate,
It looks pretty good, and will work. The only things i would recommend is to wire the whole thing in 1.5 mm2 wire (not a lot of advantage in using smaller wire), that way if your 2 amp fuse need to be upgraded, you've got plenty of room to move. I would even consider using 2.5 mm2 on the power section unprotected by the fuse as this will only be protected by the circuit breaker or fuse on your house, which could be as high as 20 amps.
You may want to look at another couple of SSR's to replace your relay arrangement for your priority supply to your HERMS and HLT. Apparently you can get normally closed SSR's which would be suitable for cutting power to your HLT when the HERMS is in service. I'll see if i can find the thread where it was detailed. If you use a relay, it's likely to get hammered by the Controller and wear our quickly (and be noisy).
Cheers
Dan

EDIT: It was in this thread, i'd say you've read it.

 

[mxd]

All three vessels are 50L.
The relays are set so that the HEX element has priority, but when it is not on, the power is allowed to be used by the HLT element.

I should also mention that with the three PIDs; the first will be used to control the HLT element, the second will be used to control the HEX element (probe on outflow) while the third will just be used to monitor the wort out of the MLT.

Mate

I found a single 2200 watt wouldn't get my single batch to a boil, have you got the kettle built yet if so give it a try or maybe consider gas for the kettle ?

 

[mateostojic]

Thanks Dan, Yeah i remember reading that you can get normally open and normally closed SSRs but i didnt realise that they would be better then the relays. I will leave room for more SSRs in my control box in case the relays fail. I have already bought the gear so for now i'll stick to the relays, but i will report on any problems i have.

mxd, thats a bit of a concern that you couldnt get a single batch to boil with 2200W. I was really banking on that. Did you insulate your vessel and did you use a lid? If the 2200W doesent work, ill have to upgrade to 2400W for the kettle as i really want to avoid using gas. I havent got the kettle vessel yet, its due to arrive today or tomorrow.

Thanks,
Mate

 

[dmac80]

Thanks Dan, Yeah i remember reading that you can get normally open and normally closed SSRs but i didnt realise that they would be better then the relays. I will leave room for more SSRs in my control box in case the relays fail. I have already bought the gear so for now i'll stick to the relays, but i will report on any problems i have.

mxd, thats a bit of a concern that you couldnt get a single batch to boil with 2200W. I was really banking on that. Did you insulate your vessel and did you use a lid? If the 2200W doesent work, ill have to upgrade to 2400W for the kettle as i really want to avoid using gas. I havent got the kettle vessel yet, its due to arrive today or tomorrow.

Thanks,
Mate

Mate,
I'll second mxd's post on the 2200W element in a single batch. I had one in my kettle, it would get to a boil (kettle was insulated) but it was a fairly pissweak one, and i think it was contributing to low hop utilisation. I ended up changing to a mongolian, goes good now.
If you've already got the gear you can always try it out and add another element at a later date if you need to.
Cheers
Dan

 

[tuckerle71]

Mate,

+1 for adding an RCD. (from an Electricians point of view)

I have been looking at setting up a 4 vessel HERMS system, so I was interested to see your design.
Some very good features in your design, like prioritizing your heating elements and adding an off switch to your alarm buzzer.

A couple of things I did note:

The wires connecting the alarms on your HERMS and HLT PID Controllers have been left out, so your Buzzer is only monitoring your MLT Alarms.

I would probably use a D.C. Plugpack for power to the Ammeter rather than the hassle of mounting a Transformer and Power Supply. (Actually, I probably wouldn't have bothered with an ammeter at all)

It may be a good idea to interlock your Heat Exchanger Element with the Pump Run Switch so that you are less likely to boil the HEX, although that might make it difficult to get to temperature the first time..

By mounting the RCD through the front of your box, you would be able to do away with the Relay and Main Switch (this has the added advantage of allowing you to hit the Test Switch to turn it off each time)

Oh, and Thankyou. If I hadn't been reading your posts, I wouldn't have known that the price of SSR's had come down so much in the last few years.

Leigh

 

[mateostojic]

Mate,
I'll second mxd's post on the 2200W element in a single batch. I had one in my kettle, it would get to a boil (kettle was insulated) but it was a fairly pissweak one, and i think it was contributing to low hop utilisation. I ended up changing to a mongolian, goes good now.
If you've already got the gear you can always try it out and add another element at a later date if you need to.
Cheers
Dan

yeah i will try it with the HLT before i drill holes in the kettle. I might add another 2200 element to the kettle and run it through i separate 10A circuit, or ill see if a single 2400W will be enough. I have a NASA burner which would boil the bejesus out of the wort, however i want the rig to be indoors...and also the place i am renting is made of wood.

Mate,

+1 for adding an RCD. (from an Electricians point of view)

I have been looking at setting up a 4 vessel HERMS system, so I was interested to see your design.
Some very good features in your design, like prioritizing your heating elements and adding an off switch to your alarm buzzer.

A couple of things I did note:

The wires connecting the alarms on your HERMS and HLT PID Controllers have been left out, so your Buzzer is only monitoring your MLT Alarms.

I would probably use a D.C. Plugpack for power to the Ammeter rather than the hassle of mounting a Transformer and Power Supply. (Actually, I probably wouldn't have bothered with an ammeter at all)

It may be a good idea to interlock your Heat Exchanger Element with the Pump Run Switch so that you are less likely to boil the HEX, although that might make it difficult to get to temperature the first time..

By mounting the RCD through the front of your box, you would be able to do away with the Relay and Main Switch (this has the added advantage of allowing you to hit the Test Switch to turn it off each time)

Oh, and Thankyou. If I hadn't been reading your posts, I wouldn't have known that the price of SSR's had come down so much in the last few years.

Leigh

Thanks for the pointers Leigh. yeah i was thinking of just using a DC plugpacks from an old phone. The powerpack cost me a whole $6 so it wont be much of a loss.
With regards to he RCD replacing the switch and relay, that is a good point. When you hit the test switch, is it as good as flicking the on/off switch for turning the rig power off? I dont really get how the test switch works.


Cheers for the valuable feedback dudes,
Mate

 

[tuckerle71]

With regards to he RCD replacing the switch and relay, that is a good point. When you hit the test switch, is it as good as flicking the on/off switch for turning the rig power off? I dont really get how the test switch works.

Basically, an RCD measures the amount of power going out the Active and compares it to the power coming back on the Neutral. If there is any difference (i.e. going through you, or a bad/wet connection leaking to earth) it trips the switch and disconnects both the Active and Neutral conductors in a fraction of a second reqiuring you to reset the RCD (i.e. turn it back on).

The test switch simulates this and trips the RCD.

Note: If it happens a second time, start unplugging things until it doesn't trip, and then work backwards.

It will be fine to use this as your on/off switch, and you're supposed to test your RCD's every month although nobody ever does...