How to PID a Silvia

7/29/2019 How to PID a Silvia

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PIDing a Rancilio Silvia- a STEP by STEP guide -

BY Warren Sullivan

Ok, just want to get a few points across before I start this guide, I am in no way anexpert on PIDs, Im a tradie and not in a trade associated with electricians, I dohowever have a good mate who is an electrician and quite a few electrical technicianfriends who helped me figure out the wiring and explained to me what does what.

The important thing is to make sure you get all the right parts when making your ownkit, PID kits supplys a perfect sleek kit with every single thing you need and its allintegrated and preset, it takes the worry out of the unknown, his kits are renownedacross the world as being the best and cleanest looking kits available for Miss Silvia,and as he is a very valuable site sponsor, I would like to extend a congrats to Jim on

producing a kit second to none, and I hope Im not stepping on anyones toes here, forme the kit was a little too expensive given the current economic climate.

Im sure if you are reading this guide, you have an understanding of the importance oftemperature stability in the brew process and in turn the need for a PID in a silvia, youhave a basic understanding of what a PID does and how it does it. If you are new tothe prospect of adding a PID to a Silvia then here is a very helpful little analogy Ifound on the net:

Imagine you are driving your car down the street at 60 klm/h. Ahead is anintersection controlled by a stop sign. If you continue to travel at 60 klm/h until you

reach the intersection, then slam on the brakes, your car is going to shoot through

past the stop sign before coming to rest. If, on the other hand, you gradually apply the

brakes well in advance of the stop sign, you can come to a controlled stop right at theintersection.


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The road to temperature stability

Now I Gronked my silvia prior to adding a PID, which if you do a search on

Coffeesnobs you will find it basically involves placing a thermocouple on top of theboiler and monitoring boiler temperatures with a Digital Multi Meter(DMM) andmanually flushing boiler water through brew head to get it to the right temp prior to

pull the shot. This worked pretty well for me, the only disadvantages were, the time ittakes to wait for the boiler to get back down to the desired brew temp and the amountof user interaction required to monitor gets a bit full on for me to produce coffee, Ifound I was pretty much dismissing anyone talking to me whilst I was makingcoffeevery anti social! but it worked well for me to produce more consistentquality shots, it was cheap as chips and it is a good interim process on the way toinstalling your own PID as you will need a thermocouple for a PID anyway!

So lets get started with the tutorial, I will give you a shopping list, cover off on gettingthe parts ready, then the install itself and finally turning it all on and a guide on how Ituned my PID to my likingHere we go!

PART 1 SHOPPING LIST

I will outline the exact products I bought for my install, obviously you can change the

basic bits and pieces for alternate brands etc but the CD101 PID has worked very wellfor me, and its cheap, I cannot guarantee its longevity of life as I have only had itinstalled for a month, but I will say that my line of work involves satellites, and asyou can imagine a lot of $$$ worth of equipment, now the cooling mechanisms in oneof our larger satellite dishes uses this same exact PID controller, a little simpler I mustadmit as it only turns on the large cooling fans within a series of control cabinets, butit has been in place for years, running 24/7and still alive! So it probably has earntits stripes there. So here is the list.

1. CD101 Controller2. K-type thermocouple

3. Jaycar Jiffy enclosure HB-60124. 2 meters of Heavy Duty 240v extension cable 15AMP simular to Jaycar WB-1568 but round5. run of the mil spade connectors times 2(big enough to fit to the HD 240vextension type cable)6. 25amp Solid State Relay(SSR)7. a cut off lamp power cable 240v, I used a 2 prong lead from a camera batterycharger.


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DESCRIPTION PHOTO WHERE FROM PRICE

1. CD-101 PIDCONTROLLER

WWW.EBAY.COM.AUJUST SEARCH FOR CD-101

PIDMINE WAS FROM CHINA,

FREE DELIVERY

$47

2. K-TYPETHERMOCOUPLE

WWW.JAYCAR.COM.AU $11

3. JIFFYENCLOSURE

WWW.JAYCAR.COM.AU

PRODUCT NO: HB-6012

AVAILABLE IN VARIOUSSIZES TO SUITAPPLICATION

$7

4. 240VAC -15AMPEXTENSIONCABLE

WWW.BUNNINGS.COM.AU $6

5. SPADECONNECTORS

WWW.JAYCAR.COM.AU $3.95

6. 25 AMP SOLIDSTATE RELAY

WWW.EBAY.COM.AU $15

7. 240VAC POWERCABLE FORSMALLAPPLIANCE

CAMERA BATTERYCHARGER LEAD

FREE!


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PPPAAARRRTTT 222 --- PPPRRREEECCCAAAUUUTTTIIIOOONNNSSS

Disclaimer: WORKING WITH 240V CAN AND WILL KILL YOU IF YOU COMEIN CONTACT WITH IT, EVERY SINGLE TIME YOU APPROACH SILVIA INANY STAGE OF DISASSEMBLY, THE MACHINE MUST BE UNPLUGGED

FROM THE WALL, IF YOU ARE IN ANY DOUBT WHATSOEVER GET AQUALIFIED ELECTRICIAN TO CHECK IT PRIOR TO PLUGGING IN ANDTURNING ON, I CANNOT EMPHASISE THIS POINT ENOUGH, I TAKE NO

RESPONSIBILITY FOR INJURY OR DEATH RESULTING FROM FOLLOWINGTHIS GUIDE IN ANY WAYYOU HAVE BEEN WARNED!!!!

PART 3 - WIRING DIAGRAM

This is a basic wiring diagram (wiring diagram below), as you can see I am not anelectrical engineer!, which is probably a good thing for you, as looking at schematics

can be confusing to the untrained eye. With the inset diagram, the wires that areconnected to the existing brew thermostat are simply unplugged then the spadeconnectors on the wires from the SSR are plugged into the female plugs that come offthe original thermostat, that is it! This is a visual guide only, the step by step guidefollows the diagram:


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PART 4 THE STEP BY STEP GUIDE

Step 1 Preparation of Silvia.

Unplug the machine, not just turn it off, unplug it and move it to an area that you canwork on it, like a large workbench or dining table(might want to use an old table clothto avoid flying objects from the other half!)As you disassemble Silvia, place all the parts out of the way completely,

Remove the drip tray cover and drip tray underneath;

Remove the group handle (portafilter in the USA) and steam knob by simply pullingout;

Remove water reservoir and shake any remaining water from hoses;

Remove the top plate with the 4 phillips screws;

Removing Water Reservoir.


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Removing Top plate - 4 screws.

Lifting and removing top plate.


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Remove the back cover screws using a small Phillips head screw driver angling it infrom the top to gently remove the small screws, then manoeuvring off the back coveraround the inner splash guard.

Removing Back Plate screws.

Remove the inner splashback that sits beside the water reservoir with 2 Phillips headscrews

Removing inner splash guard.


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Remove the front cover by removing the 4 small Phillips head screws, there are holesin the back of the mounting frame to stick your screwdriver through, and then there isone screw holding the front plate on, its inside the cover just in front of the boiler, itscrews into the brew head below the cover, you need to now remove all the wiresattached to the switches on the front panel, I recommend you do a basic wiringdiagram so you can correctly replace them later on, I have provided a wiring diagram

below but you need to confirm that the colours dont differ from model to model.Remove the front cover, leaving switches in the panel and set aside.

One of the 4 screws to remove for front panel.

Screw to remove just in front of the boiler..


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Wiring Diagram of the front panel looking at the back of the panel

You now have a stripped Rancilio Silvia, looks a little bare doesnt she!

Stripped Miss Silvia.


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Step 2 Preparation of Parts

PID and enclosure I used the larger enclosure from Jaycar just in case I decide toinstall something else in the future, like a shot timer, it gives me plenty of room tomove with plenty to spare, you could fit the PID into the smaller version with a fewmillimetres to spare, use the white mounting brace that comes with the pid to trace thesize of the hole necessary onto the front of the enclosure, this is where the PID willslide into, remember its better to be a tighter fit than too loose so be gently and carefulwith the cutout, now, I drilled holes with a drill all the way around the inside of thetracing then pushed out the plastic and squared it up with a Stanley knife and

sandpaper until it fit in nice and tight, after you have it mounted in nice and flush,remove it and set the PID and enclosure aside.

The cutout for the PID to slide into.


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Wiring SSR to Boiler - now this is a little bit of guess work, cut about 60 cms of the240v cable off and cut the cable to remove the 3 wires by slicing the outer sheath, youmust not penetrate the wires inside the outer cable, this WILL make the wire.lets

just say a little dangerous! So take care!Pull the wires out individually by hand, you will only use 2 of the 3 wires, brown and

blue, discard the green wire and outer sheath. Bare all 4 ends of the 2 wires but onlyabout 8mm max. The crimp on the 2 spade connectors to one end of both wires as

pictured below;

One end bare, one end with spade connectors crimped on.

Wiring SSR to PID (control cable) youll need to leave about 1 meter for this one,bare one end of the cable by slicing gently to remove the outer sheath and exposingthe inner wires protruding about 3 cms, bare the brown and blue wires by cuttinggently and removing their sheaths, only expose a max of 1 cm of this wire, and twist

the inner wire tight. I cut the green wire at the outer sheath level because I didnt useit, obviously, as you will only need two of the three wires.

Brown and Blue exposed, green cut flush.


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2 Prong Power Lead power to PID I found a power lead that plugs into a AAbattery charger and simply cut the connection off the end, not the end that plugs intothe wall, the other end, you could also use a desk light lead or any other 2 prong

power lead laying around the house.

Power cable for PID, from a AA battery charger.

K-Type Thermocouple PID to boiler top If you get the K-type with the end to pluginto a DMM, simply cut off the connector and bare the metal wires, expose only about4mm of this delicate wire. (Take note of the polarity of the wire colours).

Cut off DMM connector, note polarity of wires to colours.


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Step 3 Install the SSR and Wiring to boiler.

Time to mount the SSR, the best place I found to mount it, needing no modificationswas behind the splashback as pictured, I simply removed the screw that holds theSilvias power cable on the back of the centre plate and screwed it in from the frontside of the centre plate as pictured, this now serves two purposes, it now holds theSSR in place securely behind the slash plate and it still holds the power cable in place

behind the plate!, perfect! Make sure the SSR is mounted so that the 2-32VDC inputis at the bottom, just thought this would be a good safety measure given the DCvoltage closer to the bottom of the splashback, dont really know if it matters but ohwell, its a thought!

Undo this screw from the back of the machine and screw it in from the front to holdSSR.

Attach SSR with Screw, tighten well.


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Now grab your two 60cm wires with the spade connectors on one end, as picturedconnect the uncrimped ends to the top side of the SSR as it sits mounted, you canfollow my wiring colours if you want, not sure if it makes a difference with this onethough as I believe the SSR acts as basically a switch, I placed the brown wire in 1and the blue wire in 2 as pictured.

SSR to Boiler wires in place.

Now run the wires up through the back of the splashback and along the existing wiresthat lead to the top of the boiler, dont zip tie just yet, just run it along with them as

pictured, you want the end of the wires with spade connectors sitting around theexisting brew thermostat with a little spare length to play with as pictured.

Guide the wires up to top of Boiler, follow existing wiring loom.


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Wires all the way up, temp zip tied to keep in place.

Now the Brew thermostat is the one sitting on the left as you look at the machine fromthe front, thats the one you want, (the other one is the steam thermostat), disconnectthe two cables from the brew thermostat and connect the brown wire from the SSR tothe two red wires that you have just disconnected from the thermostat, and then the

blue wire goes into the other grey wire off the thermostat, the existing thermostat isnow left totally disconnected and will no longer be used at all. Now you have the SSRmounted and wired in to the Boiler wiring. All as pictured below

Disconnect this one which is red red on thermostat and connect to Brown wire fromSSR.


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Red Red wire from Boiler Thermostat connected to Brown from SSR with spadeconnector.

Disconnect this one which is Grey on thermostat to Blue from SSR.


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Grey wire from Boiler Thermostat connected to Blue from SSR with spade connector.

Step 4 Installing the Thermocouple.This is quite simple, I have a picture indicating the screw I used to attach thethermocouple to the boiler, there are a multitude of opinions on where the TC should

be mounted..on the lefton the right???? So I just picked a happy medium andmounted it in the middle, simply unscrew it, separate the wires just behind the

thermocouple bead, place the thread of the screw through the gap in the wire andreinstall the screw into the boiler, be really careful not to crack the bead on the end ofthe TC, soft hands! The mounted TC is visible in several photos, if you need a better

pic just email me and ill send it to ya. Run the TC cable down the same wires you ranthe Boiler to SSR cables along before but poke the cable down through the hole in thecentre wall and out to the back of the machine, well deal with the rest in the nextstep, zip tie the Boiler to SSR wires and the TC cable to the existing cables so its niceand neat with no excess wire hanging around..as pictured below;


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Unscrew this one.

Separate the wires and place in screw.


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Thermocouple installed, best to place it directly on the brass under the thermostatbrackets(unlike mine, I have changed this since).

All wired up and Zip-tied.

Step 5 Installing the SSR to PID wire.

This can be done in a variety of ways, I wont gabble on too much with this as thepictures do most of the talking, I have the cable exiting the machine in the little gap inthe rear corner of the machine, which works well as it is totally reversible if I ever

decide to sell, Ive seen variants with holes drilled in the back of the black mountingframe and the cable coming out of there and up to the PID, and some even drill holesin the stainless!, no thanks!


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I will just briefly run over the connection to the SSR, run the extension wire throughthe machine behind the pump, up through the hole then over the centre wall of themachine and head down to the SSR, loop the cable around under the SSR and connectthe blue wire to negative (-) and the brown wire to positive (+) as pictured. Make sureall connections are tight on the SSR and place on the clear plastic cover, get rid of anyextra slack on the cable running through the machine, tip tie the cable to the water lineat the back of the wall, and zip tie the rest of the cable so it is held off the boiler and Is

quite solid, you dont want anything in this install to vibrate and move, it should looklike the pictures below;

Entry for PID to SSR wire (tight squeeze).

Run behind pump and up water line, through hole and over wall.


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Over wall and loop down under SSR, Connect and tighten well.

Zip Tied in place, make sure the pump is not interfered with.


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Now as it sits you have the SSR installed and wired up to the boiler and a Controlcable zip tied safely running through the machine exiting out the back left hand cornerof the machine, leave the TC cable hanging out the back for now, we will deal withthis later on, note where it is running in the above picture.

Step 6 Wiring up and installing the PID.

Grab your enclosure, drill a hole or holes big enough to fit the cables through theback, that is the control cable, the TC cable and the light extension cable with the 2prong wall plug, you can drill the holes where ever you want it to go, I choose to enterfrom the top rear panel to allow for additions, now I also chose at this stage to havethe TC cable exit the machine as pictured below, this was mainly because of thelength of the TC I used, Im looking at installing a RTD sensor soon so I did this as a

interim measure.Push the control cable, the power cable (tie a knot to prevent cable strain on the pid),and the TC cable through these holes and right through the PID hole you drilled andfiled out at the start, and connect as follows:

(These will only apply if your wiring is the same colours as mine, remember thesheaths on TC cable can be different colours, they vary from model to model, if youconnect the TC incorrectly the PID will display temps in reverse, so when it is heatingthe temp will appear to decrease, simply reverse the two TC cables around and all will

be good!(if you cut the DMM connector off the TC take note of the polarity)

Control Cable:Brown to connection 5Blue to connection 6

Power cable:

Brown to connection 1Blue to connection 2

Thermocouple:Red to connection 12Yellow to connection 11

Now simply push the PID back through the hole so it fits snug, move cables around tosuit. Place on the cover of the enclosure.


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Control, power and TC cable running into enclosures rear.

Tie a know in the power cable to provide tension relief.


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All wired in as per instructions above and the user manual.

Push PID back into hole and replace cover on enclosure.


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Your PIDed Silvia.something missing, oh yes, her clothes!

You now have a PIDed Silvia!

Step 7 Refitting and cleaning up

Reconnect the switches on the front with the supplied wiring diagram and replace allpanels, remember the exit site of the TC wire if you choose to go down that road.I used heavy duty double sided tape from bunnings to stick the PID to the side ofSilvia and it has worked really well, not showing any signs of falling off, some maychoose to bolt on the enclosure, but as I said before I prefer the process to bereversible.

Step 8 Check and re-check and re-check again!

Check everything, make sure everything is secure, all connections are tight andnothing is where it shouldn't be, get it all checked by an licenced electrician if you are

not too confident.

Your PIDed Silvia, ready to go!


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Step 9 Turning it all on!

Now that your 100% sure everything is hooked up correctly, fill the reservoir, makesure all the switches on the front of Silvia are turned off, plug in the machine and thePID, turn it on at the wall, you should see the PID spring to life and display a settingsscreen for 2 seconds this will show you what type of TC you have connected and the

temperature measurement, which is Celsius by default, then it will display the rangeof the device, with a K-Type it will be 400, now the first thing to do is an auto tune,you will have to wait for silvia to warm up completely, so give it 45 mins.

Now with the auto tune, hold down the menu button for about 4 seconds till thedisplay shows the configuration menu, the first setting you will see is the alarm, I setthis to 150 Degrees, I dont use it but I believe you can hook something up to it as anaudible alarm, good idea to avoid leaving the steam switch on!Hit menu again and it will display ARU, Autotuning, hit the up arrow to set it from 0to 1, then hit menu again, it will now go through its autotune function, this will takeabout 7 mins.After running the autotune, all I did is tweak the PID settings a little to get the desired

result, to be able to do this you need to have a basic understanding of what does what,I found this on the net, it was the best in regards to helping me understand what I wasadjusting, this covers off on the P, I and the D settings;

PThe Proportional band is proportional to the error measurement (set temperatureminus actual temperature) essentially your margin of error. The Integral portioncontrols the response time of the heater in response to the Proportional band. I am set

at 205.6, my probe says the medium being monitored is 205.4. Ooops, that is out of

my Proportional band range (error), I need heat. Or reversely, my temp setting is

205.6 and the medium being monitored is 205.9, oops, time to stop. Now I sit herewhile my temperature carries over another 1.0 degrees and then starts to fall. Ooops,

now I am at 205.4 again, time to heat, over and over and over. Little more than a

thermostat at this point.

I

Now the I comes in, Integral action. Basically a measurement of time. So now I can

compensate for time error in the above loop. So now my little brain says Ok, you wantme to run at 205.6, I am at 205.2. You want me to heat this stuff back to 205.6 but not

go over (reverse the process for cooling). So I know that if I apply heat for 1 dividedby I (lets say 0.6 seconds) I will heat the stuff to 205.5 but I know there will be carry

over heat for another 0.5 seconds so I will turn off the heater even though I am underthe error margin and the temperature will coast up to 205.7 and stop instead of

running up to 206.9.

D

Now the Derivative jumps into the party. Basically doing the opposite of the above

action. Ok, you told me to run at 205.6, I heat for 0.x seconds and turn off I know my

temperature will stop at 205.5 and my end error will be 205.7. Now I sit here. Oops, Iam back at 205.2, time to juice it up again. But I know that if I heat for 0.x secondsonce I am beyond my margin of error I will get where I want to be. Hmm, but I know I

am going to cool Z fast so instead of waiting until I get past my error setting I am

going to kick in the juice to minimize the drop.


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SummarySo P tells the brain I am beyond my error margin. I, tells the brain how long to apply

juice before I need to turn off to keep a tighter band and D tells the brain how long to

wait after before I give it more juice to keep the temperature from falling too much

Now I read a tonne of stuff on the net about PID settings but that was the bestexplanation I could find.I did my Autotune, and I found that after pulling a shot, the temp would overshoot theset temperature by about 8 degrees, so after reading the extract above I realised Ineeded to tweak the I in PID, so I raised it to compensate, after about 5 or 6 changesand a bit of trial and error I got it, here are my current setting from top to bottom;

Parameter Description Default Setting My SettingALM 1 Alarm, Set to

Desired Degrees,can be hooked up

for audible alarm

50 150

P Proportional BandAs per abovedescription

30 34

I Integral TimeAs per abovedescription

240 165

D Derivative TimeAs per above

description

60 20

Ar Reference ValueSet AutomaticallyAfter Autotune

25 100

r Heat-ResetProportioningCycle

20 3

Pc Cool sideproportional band 100 2

db Deadband 0 0

B Cool sideproportional cycle

20 20

P6 PV Bias/Offset 0 0


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I Found that Bracketing was the best method to get to the right settings, and bybracketing I mean, trying a setting eg setting 50 for Integral, pulling a blind shot, thenchanging it to 300 and then pulling another one and working toward the perfectnumber, which for me was 165, a bit of trial and error and youll get there.

Basically what you want to end up with is a machine that will return to the Settemperature without overshooting or taking too long, it will do this by turning the

boiler on and off so it arrives at the desired temp without overrunning, and thatsimportant, my setup allows me to pull a shot, and within 30 secs the temperature willreturn to the set point and I am able to pull another, its working really well for me,dont know what I did without it!

After steaming and purging the boiler to a temp below 100 degrees it will take about2-3 mins to return to the set temp without overshooting.

In conclusion, this project has been tonnes of fun, and it cost next to nothing, thedifference in my shots is amazing, i can now change the temperature depending on the

bean im using at the time, its incredible the different tastes I can get with differenttemperatures, I would recommend anyone contemplating installing a PID, DO IT, itsso worth it. Best of luck in your install, any questions at all please email me as Ill bemore than happy to answer them, you can catch me at [email protected]

GOOD LUCK!

How to PID a Silvia

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