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AllGrainNZ
07-13-2015, 02:03 AM
Hi All.

I'm looking for a bit of advice before I order my main brewing, CIP and keg washing pumps.

We're about to upgrade from a tiny 1BBL brewery to a 10bbl Frankenbrew-type system (awesome book Tom). The kettle and mash tun are converted dairy tanks and the hlt will just be a small (500L ish) insulated holding vessel on top of the mash tun - strike water and sparge water to be heated in the kettle and pumped to where it's needed.

During sparging, the sparge water will fall on to the grain bed using gravity and the runnings will fall into a grant, also using gravity, from whence they will be pumped into the kettle.

We have a few fermenters and brite tanks en route from Gavin Zhang of Sungood Machinery plus a couple of older vessels repurposed from a winery. Fermenters are dimple jacketed and the brites will be stored in a cool room.

We have 80 odd kegs already and expect to have another 100 or so before the end of the year.

My question is; Will I need a VSD / VFD on at least one of my pumps? I've gotten quotes from a few (NZ) suppliers and I like the look of the Lowara CEA 80/5 1.1HP pumps. The recommendation was for a single phase on a pump cart for keg cleaning, CIP, and backup for brewing, and a three phase with VFD for brewing.

My main question is whether the VFD is actually worth it? Where during the brewing process will I need this much control over the flow rate?

Also will I need a transducer? And a pressure tank?

Thanks in advance for your help

Karl Hayes
Te Aro Brewing Company
Wellington
New Zealand.

Starcat
07-13-2015, 07:22 AM
Karl, VFDs can be useful but we got by for very many years without them. IN some cases they are being over used and over rated by the fanciful.
With that said, I do like them in many instances, but our Brewmaster is old school on the Brewhouse system. So in that case you generally have a throttling valve on the pump discharge to control flow through the chill down HX. For 1 HP CIP pumps of similar design to the Stock C-114, drives are mostly not necessary, but certain scenarios can make them helpful. Also you need 3 phase motors to utilize drives. When you get into larger pump horsepoewr and impeller sizes having the variable speed capability becomes more helpful, especially in getting cleaning chemicals into larger vessels before you re-patch and recirculate. We use simple single speed 1 HP CIP pumps for everything up to 60 BBL tanks, and they can be used on the brewhouse in a pinch if necessary.

http://www.spx.com/en/waukesha-cherry-burrell/pd-wcb-centrifugal-pumps-cseries/

TGTimm
07-13-2015, 12:00 PM
While I often agree with Warren, this is one place where I'll disagree. VFDs are not essential, but they are beyond useful. Call me fanciful, but I've been building and keeping an increasingly successful brewery running for over 15 years now.

Standard Ball and Butterfly valves are not meant for throttling, and aren't very good at it. Very small changes in handle positions result in very large changes in flow--and they don't tend to stay where you put them. Too much monitoring. Set the speed on a VFD and it's going to stay right there.

VFDs are getting pretty cheap--especially if you don't have to have a wash-down enclosure, or can simply put the VFD in one. While larger units require 3-phase, most units for 1 hp pumps can take a single-phase input and output 3-phase.

VFDs add an important layer of protection to your expensive motors--among other things, phase-monitoring and shut down for phase imbalance/loss/brown-out. Very important if your electrical supply is less than perfect.

VFDs add flexibility for future automation. At some point, I'll be linking our knock-out pump VFD to a temperature controller so we can keep our knock-out temp constant without monitoring.

We don't, for the most part, use the very expensive VFD-rated motors--and our motors still last a very long time (knock on wood--I probably shouldn't have written that).

A 1 hp pump may not really need one, but our Vorlauff/transfer pump is a 1 hp C114, and the VFD for it isn't something our brewers would be happy doing without.

Our brewers rely on our VFDs to the point that I keep spares on hand--we're remote and getting replacements takes too long. I've had two previously used VFDs break down in the 15 years I've been here.

While you may be able to run for years without a three-phase feed to your brewery, you'll want/need it as you grow. Most of the professional equipment you'll need to play with the big dogs will be 3-phase. Plan ahead.

Bainbridge
07-13-2015, 12:19 PM
VFDs are not 'essential' but fall quite firmly into the 'extremely useful toys' category. We have one on our wort pump and one on our mobile pump. We just got a grant from our power company to add one onto our glycol recirculation pump too.

Each of these procedures has a particular speed it likes to go at on the vfds:

Wort transfer during sparging
Whirlpool speed
Cast-Out speed, which also changes seasonally with our groundwater temperature
Grant to Kettle and Kettle to HeatX to Grant during post-brew CIP (we rig the whole thing to clean everything at once using two VFDs set at two different ideal speeds)
Dry Hop recirculation in the tanks (slow)
CIP through spray balls (fast)
CIP of racking arms (slow)
Filter runs (Fast, or slow it down incrementally if we start building back pressure from clogged pads)
Transferring out of barrels

We keep a paper up on the wall that has the current 'best speed' for each of these, and update it as needed. You could do it by throttling the outflow valve, but your control is waaay less precise.

And it keeps the pumps quieter, since they're not at full blast all the time.

AllGrainNZ
07-13-2015, 09:36 PM
Thanks guys

For the record, I've purchased a three phase 1.5HP with VFD and a single phase 1.1HP without. When funds are a little less tight (common refrain of the start-up brewer) I'll buy a spare three phase setup.

Slainte

Karl Hayes
Te Aro Brewing Company
Wellington
New Zealand.

Starcat
07-16-2015, 11:34 AM
Hey Timm, I would truthfully rather see a VFD control on the Brewhouse, but the Brewmaster does not care for them in that position for some very specific reasons.
The throttling valve they are using is made for that purpose, butterfly style with fine adjustment. As with many things I think they can be carried too far in some cases, but I agree with your treatise almost 100%. There are certain applications where they will add an extra layer of complexity and potential failure to. The point I was attempting to make is that some people seem to have the idea that they are the answer to every pumped system application which can not necessarily always be the case in my experience. There are also attempts to use drives to solve problems without going to the root of the matter first.
I see it as a matter of preference for the systems in question and also the setting.

Sincerely

gitchegumee
07-16-2015, 07:40 PM
These guys hit all the major points in favor of VFDs. The cost of a VFD is almost as low as simple motor protection that you would need anyway. I have seen a few instances where the identical motor is on a CIP cart, a grain mill, grant pump, etc., and a single VFD was fed to a receptacle that allowed one device many duties. For sure I'd use one for vorlauf as I agree with Timm that butterfly or ball valves make terrible throttling valves--even when they are "made for it" by adding a goofy micrometer adjustment for the valve stem (and are impossible to turn off quickly when something goes to hell, too). That doesn't change the nature of a ball or butterfly valve. They still aren't much good at throttling flow. And when used for that purpose, tend to be harsher on the wort than a gently VFD-controlled pump. But as Warren said, they do add another layer of complexity and failure that a simple valve avoids.