inkstar Senior Member Joined: 26 Sep 2006 Posts: 55 Location: Atlanta Expertise: I live coffee
Espresso: My Sweet Girl - Silvia Grinder: KA Proline - modified Vac Pot: Yama Drip: Pour over, Apress Roaster: rk drum, hot air
Posted Tue May 1, 2007, 2:15pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
First, I apologize to anyone for getting off topic, I hope Douglas doesn't mind. Also, I am by no means an expert, and even if I were, I don't want to get too technical. My focus is what's in the cup. So how does and RTD vs Thermo affect what's in the cup? In my experience, RTD's are much more stable. I realize this may mean very little if you get the correct param for your P, I, and D, but trying to find the perfect params in order to counter the Thermo's quick jumps is daunting. I usually fall asleep whenever I use a PID simulator. RTD's do not have the problem of quick jumps because the change is so stable. Sit and watch a PID w/ a thermo next to a PID w/ an RTD and you'll see far more jumps with the thermo. Now, the real question, does it affect the cup? In my opinion is does affect the consistency of the cup, and RTD's are better, that's why I suggest RTD's. Now the other side of the story. RTD's cost a bit more, not much though, and some believe the quick response is necessary to energize the heater as soon as the shot starts. I think using a relay to energize the coil the moment you start the shot is a better solution. Now for 3 vs 2 wire, again I don't wanna get too technical, but no, it makes no difference. Actually, I don't think 3 wire even has a place in the world because once you get out far enough for the resistence in the wire to matter, you should use 4 wire instead. I used 3 wire on my silvia because that's what I had, but I just installed a 2 wire on another machine and see no difference. Oh, and you really should external mount all electronic controllers, they are affected by heat, regardless of rated operating temperature, so better safe than sorry. Drill vent holes in your enclosure. As for the CAL 3300, I must say that I think all PID's will be effective and Craig is 100% correct in saying you get what you pay for. So go buy whatever you like, if it costs more, it's either better or has a lot of features. I think the CAL 3300 has a Ramp/Soak, I could be wrong it may not, but if it does, you're gonna pay extra for this feature and it won't be used.
rainham Senior Member Joined: 18 Apr 2007 Posts: 18 Location: Toronto Expertise: Just starting
Posted Tue May 1, 2007, 4:08pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
im currently awaiting a members sylvia (old style) and will be PIDing it ala the gooseneck tail method utilizing murphysonline.com info (wiring) for most part i believe. i will post here for any feedback or advice as it goes along (maybe i should start a new thread?). my first concern is in regards to drilling out a hole in the back to mount and run wires through gooseneck and ultimatly to fugi pxr3 PID.
thanks again for any and all info anyone can offer up before i get out the scalpel and mask!
inkstar Senior Member Joined: 26 Sep 2006 Posts: 55 Location: Atlanta Expertise: I live coffee
Espresso: My Sweet Girl - Silvia Grinder: KA Proline - modified Vac Pot: Yama Drip: Pour over, Apress Roaster: rk drum, hot air
Posted Tue May 1, 2007, 4:33pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
Don't be concerned, just make sure you know what you're drilling into, use a punch and a Uni-bit, you'll get better results. Just a note though, side mounting is very easy, even tapping the holes for screws, http://www.flickr.com/photos/inkstar/439096851/ . You can also use a bracket that attaches to the screws on top and run the wires around through the bottom without any drilling or alterations to Silvia at all. PIDing Sillvia should require NO alterations at all. *disclaimer* I have not looked at the older style Silvia in a while but I believe this is true for them too.
Posted Wed May 2, 2007, 7:12am Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
Inkstar,
Thanks for the info, that's very useful stuff to know. To everyone else, I apologise for the slight digression, but I thought it was worth asking the questions given the context, and the mention of RTDs over thermocouples.
I probably should have said that my personal choice of PID, the CAL 3300 was more about the excellent deal going on a particular quality controller at a particular time, rather than an overall choice based on say not paying more for features I wouldn't actually use. It works well in my Zaffiro (as an external mount I might add) so far, although I know I could improve the recovery time by playing some more, both with sensor positioning and parameters. I may well try an RTD at some point for comparison.
Jon
inkstar Said:
First, I apologize to anyone for getting off topic, I hope Douglas doesn't mind. Also, I am by no means an expert, and even if I were, I don't want to get too technical. My focus is what's in the cup. So how does and RTD vs Thermo affect what's in the cup? In my experience, RTD's are much more stable. I realize this may mean very little if you get the correct param for your P, I, and D, but trying to find the perfect params in order to counter the Thermo's quick jumps is daunting. I usually fall asleep whenever I use a PID simulator. RTD's do not have the problem of quick jumps because the change is so stable. Sit and watch a PID w/ a thermo next to a PID w/ an RTD and you'll see far more jumps with the thermo. Now, the real question, does it affect the cup? In my opinion is does affect the consistency of the cup, and RTD's are better, that's why I suggest RTD's. Now the other side of the story. RTD's cost a bit more, not much though, and some believe the quick response is necessary to energize the heater as soon as the shot starts. I think using a relay to energize the coil the moment you start the shot is a better solution. Now for 3 vs 2 wire, again I don't wanna get too technical, but no, it makes no difference. Actually, I don't think 3 wire even has a place in the world because once you get out far enough for the resistence in the wire to matter, you should use 4 wire instead. I used 3 wire on my silvia because that's what I had, but I just installed a 2 wire on another machine and see no difference. Oh, and you really should external mount all electronic controllers, they are affected by heat, regardless of rated operating temperature, so better safe than sorry. Drill vent holes in your enclosure. As for the CAL 3300, I must say that I think all PID's will be effective and Craig is 100% correct in saying you get what you pay for. So go buy whatever you like, if it costs more, it's either better or has a lot of features. I think the CAL 3300 has a Ramp/Soak, I could be wrong it may not, but if it does, you're gonna pay extra for this feature and it won't be used.
inkstar Senior Member Joined: 26 Sep 2006 Posts: 55 Location: Atlanta Expertise: I live coffee
Espresso: My Sweet Girl - Silvia Grinder: KA Proline - modified Vac Pot: Yama Drip: Pour over, Apress Roaster: rk drum, hot air
Posted Wed May 2, 2007, 10:36am Subject: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
ok now to really get off topic and get way too technical. I had a thought last night that if you couple a ramp/soak operation with a process timer, you would be able to tune the ramp/soak to start the heater at the start of the shot and ramp to the next Sv, then at another point, soak down to the initial Sv until you've reached the end of the process time, then have the timer exit the ramp/soak process. This would force the heat on to ensure all the water coming in is heated, but you'd still be able to tune the soak period to avoid overheating the water. When you get the CAL give it a try! I don't have a PID w/ ramp/soak handy, and i'd not considered it before, but it may work wonders! Has anyone done this?
Posted Wed May 2, 2007, 8:59pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
I'm just wondering what the major operational difference is between something from, say the Watlow range, and one of the cheaper controllers that sell for $40 - $60 through e-bay?
Posted Thu May 3, 2007, 1:03pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
inkstar Said:
ok now to really get off topic and get way too technical. I had a thought last night that if you couple a ramp/soak operation with a process timer, you would be able to tune the ramp/soak to start the heater at the start of the shot and ramp to the next Sv, then at another point, soak down to the initial Sv until you've reached the end of the process time, then have the timer exit the ramp/soak process. This would force the heat on to ensure all the water coming in is heated, but you'd still be able to tune the soak period to avoid overheating the water. When you get the CAL give it a try! I don't have a PID w/ ramp/soak handy, and i'd not considered it before, but it may work wonders! Has anyone done this?
So the idea here is to try and make the PID response more aggressive during the shot because you know that you're pulling in cooler water ? And you'd pick the higher Sv to try and compensate for the losses during the shot, so you're nearer the ideal Sv when you finish ?
It certainly sounds plausible, I know some folk like to hit the steam switch on their single boiler machines at some point during the shot to aid the recovery. I guess this is a more controlled and automated solution. The boiler on my Zaffiro is pretty large, so I've not had any complaints over the temperature during a shot, but recovery afterwards is a slightly different matter, which I've always thought could be handled by having a wet thermocouple in the boiler itself.
The CAL is already mine, installed and working pretty nicely. I'll re-read the manual pages on ramp/soak. I don't think it has any method of externally triggering the ramp/soak program, I think it just starts when the original Sv is reached, which probably isn't good enough.
inkstar Senior Member Joined: 26 Sep 2006 Posts: 55 Location: Atlanta Expertise: I live coffee
Espresso: My Sweet Girl - Silvia Grinder: KA Proline - modified Vac Pot: Yama Drip: Pour over, Apress Roaster: rk drum, hot air
Posted Thu May 3, 2007, 6:38pm Subject: Re: Going for the PID kit for Sylvia from Jim Gallt...Please confirm this is wis
I only have a second, but yes, the recovery after the shot is the purpose. Using the ramp/soak may be a replacement for using the steam switch or an aux. relay that turns the boiler on during brewing. It's important to note that the thermostat kind of does this on a stock machine, but adding a PID will alter the timing. The idea is to instantly turn the heater on the moment the brew begins and keep it energized throughout the pull. The Zaffiro may behave differently because of the E61. I feel like we've entered an alt.coffee discussion. Ok, gtg.
This is not universally the case. The stock stat typically does not kick back on until boiler temp has dropped below 200F. Rarely will a shot cause a drop that low (unless the shot was started with a relatively low boiler temperature).
You can tune the PID to respond more aggressively by reducing the proportional band (P), but this may result in undesirable oscillations in temperature while idling, as well as increased overshoot on shot recovery.
Intrashot temperature profiles that I have recorded (for generic 2.5oz/25sec shots) almost always show a mildly rising temperature on Silvia's - without doing anything to override PID control.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
= No New Posts since last visit 