Advertisement
Help Keep Boards Alive. Support us by going ad free today. See here: https://subscriptions.boards.ie/.
If we do not hit our goal we will be forced to close the site.

Current status: https://keepboardsalive.com/

Annual subs are best for most impact. If you are still undecided on going Ad Free - you can also donate using the Paypal Donate option. All contribution helps. Thank you.
https://www.boards.ie/group/1878-subscribers-forum

Private Group for paid up members of Boards.ie. Join the club.

EMI filter

  • 14-09-2023 04:57PM
    #1
    Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭


    I need an EMI filter folks, my booster pump is creating electrical noise and causing other devices to go offline. It already has a filter fitted within the control box, but I'm guessing that it's bust from the heat as it's 17 years old. I recall that EMI filters were available years back, a plastic can type arrangement with three wires coming out, but I can't seem to source them from electrical suppliers around here.

    Where might I pickup a generic filter or is RS my best bet?



Comments

  • Registered Users, Registered Users 2 Posts: 4,957 ✭✭✭kirk.


    ..



  • Registered Users, Registered Users 2 Posts: 4,957 ✭✭✭kirk.


    ..



  • Registered Users, Registered Users 2 Posts: 170 ✭✭Dave_D_Rave


    Try and replace like for like if possible.

    By obtaining a generic filter this may or may not solve the issue

    The filter on the pump has been specifically designed to minimise the the effects from the pump.



    Would you have a photo of the filter by any chance ?



  • Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭10-10-20


    It's a pig to get in at, but I know that it's wired in series with the motor on the neutral (only two terminals), so must be a basic coil and cap variant. Any of the ones online are on the L and N, which is better for EMI anyway. I'll see if I can reach it today.



  • Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭10-10-20


    Pah! This is the part, I think mine is a 7uF:

    The four push connectors on the top are actually just two and two shared.

    So this is a actually a start capacitor and not an EMI capacitor, would I be correct? So given that the pump is functional, can I go ahead and install an EMI filter in series with L & N before this...? I think so.



  • Advertisement
  • Moderators, Home & Garden Moderators, Technology & Internet Moderators, Regional East Moderators Posts: 12,715 Mod ✭✭✭✭2011


    What brand of pump is it? You may be able to get a replacement.

    I have found this crowd to be good for pump parts:

    https://www.domesticpumps.ie/



  • Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭10-10-20


    Yes, I found the part (posted above), but that's listed as the 'starting cap' and not an EMI cap. I'm not sure that it will resolve the EMI issue, so considering getting a specific EMI filter to add onto the pump as close as I can mount it.



  • Registered Users, Registered Users 2 Posts: 170 ✭✭Dave_D_Rave


    EMI filters are made up of capacitors and inductors which are connected in series and parallel.

    If the component you are looking at is a Capacitor only like the product you have linked above then this is a start capacitor as you have noted.


    An EMI filter will look like the attached take note of the schematic showing the caps and inductors.







  • Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭10-10-20


    That one is roughly what I'm looking for as it has the class x and class y caps to earth. Just seems to be tricky to get hold of em. Might try sorce one from an appliance store as they appear to keep them as spares.



  • Registered Users, Registered Users 2 Posts: 2,051 ✭✭✭whizbang


    Its more likely you have a bad (corroded/loose) connection somewhere along the line..



  • Advertisement
  • Registered Users, Registered Users 2, Paid Member Posts: 9,627 ✭✭✭10-10-20


    Hi, thanks. I've inspected the pump wiring, it's solid that I can tell. I'll try a closely coupled EMI filter if I can source one and see if it improves matters.



Advertisement