Results 1 to 14 of 14
Like Tree4Likes
  • 2 Post By Dimal
  • 2 Post By eamon80

Thread: Conti 100cc 2 group machine making the generator surge on the coffee van

  1. #1
    Junior Member
    Join Date
    Mar 2015
    Posts
    5

    Conti 100cc 2 group machine making the generator surge on the coffee van

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hi Everyone,
    We recently bought a second hand coffee van (about 2 years old), It's setup really nicely but once the machine gets up to 120c it makes the generator surge quite a bit.The temp goes back and forth between 119 and 120. It only durges at 119. We had the generator serviced, the carburetor sonic washed and while this made it a little bit better the surging is still there. Needless to say it's very annoying and I won't start trading as it is. We had a bigger 8kva generator plugged into the truck and it did the same. The current generator is a 7kva honda EM inverter 70is. Next thing to try I think is a different coffee machine but I thought to ask if anyone had a similar problem or have a suggestion. Thanks in advance.

  2. #2
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930
    It sounds like there's an issue when the pressure stat disengages. That's about the correct temperature for the boiler at 1.0 bar or so. The generator is supplying, maybe,3 .4kW to the heating element which abruptly stops. And starts and stops. This is hard on generators. I recommend you speak with an electrical engineer - a generator sales rep won't know enough. Big loads will always cause a small generator to surge when the contactors close and current flows to the element.

  3. #3
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930
    Addendum: change pressure stat. That may help a bit.

  4. #4
    Junior Member
    Join Date
    Mar 2015
    Posts
    5
    Thanks heaps. did you mean a relay on the electronic board?

  5. #5
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930
    Actually, the pressure switch. If it's a contactor pressure switch. There are relay pressure switches too. You will have one or the other on the Conti.

    The contacts take a beating: arcing and sparking; slag and carbon. I recently replaced a contactor that had two melted poles/contacts.

  6. #6
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930
    ImageUploadedByTapatalk1427494482.599939.jpg

    Here's a 3 pole P/stat for your Conti

  7. #7
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930
    Oops! The moderator won't like the commercial link: have quick look before I delete it

  8. #8
    Junior Member
    Join Date
    Mar 2015
    Posts
    5
    Thats great thanks again

  9. #9
    Senior Member GrahamK's Avatar
    Join Date
    Jun 2009
    Location
    Ormiston - Brisbane
    Posts
    542
    Quote Originally Posted by sprezzatura View Post
    Oops! The moderator won't like the commercial link:
    CoffeeParts are a CS sponsor

  10. #10
    Senior Member sprezzatura's Avatar
    Join Date
    Dec 2013
    Location
    Hervey Bay, QLD
    Posts
    930

    Conti 100cc 2 group machine making the generator surge on the coffee van

    This being the case, Pedro will be pleased: eamon, you can buy a three-pole Sirai pstat from Pedro Lara @ CP.

  11. #11
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,771
    There's not a lot you can do when the load being switched is about 50% of the rated output of the generator.

    Something that could be done but may be deemed more complex than desired, would be to have an appropriately qualified and licensed person, fit three high quality Pressurestats (one for each heating element) that have a very narrow dead-band setup with appropriate logic and wiring to separate SSRs connected to each Boiler Heating Element.

    This way, and for most of the time (except at start-up), only a single element will be getting switched at around 1.2KW, which won't cause too much of a problem with the generator. As more heating input is required, additional elements will be switched on as the individual p/stats detect falling pressure in the Boiler. As each successive element is switched on, the additional 1.2KW loading won't cause the generator too much grief, and may in fact be barely noticeable.

    This may sound like unnecessary complexity but all in all, a competent person could accomplish this in quite a short time and thereafter make life for your generator (and you perhaps) much less stressful...

    Food for thought perhaps,
    Mal.

  12. #12
    Junior Member
    Join Date
    Mar 2015
    Posts
    5
    We have also discussed downgrading the element

  13. #13
    Junior Member
    Join Date
    Mar 2015
    Posts
    5
    Just a quick update : I took the machine to Alex at Expobar and he found out that it is actually the computer board turning and electronic pressure stat on and off too quickly thsts causing the surging. He swapped out the relay for an analog pressure stat and the problem is sorted. Thanks everyone for your thoughts.
    Dimal and sprezzatura like this.

  14. #14
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    16,771
    Behmor Brazen - $249 - Free Freight
    Good outcome Eamon...

    One thing this exercise has highlighted, is just how difficult it can be to troubleshoot a (seemingly) complex problem via remote control. It's always much better (and easier) when the equipment is there, right in front of you.

    All the best,
    Mal.



Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •