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  1. Y

    Changing original 32Amp contactors for solid state relays?

    Hi Guys, My underfloor heating has 3 x 32amp contactors. They make a hell of a thump when opening and closing. Bit of a hum also. I'm looking at the idea of changing them for solid state relays like this one Solid State Relay - 40A (3-32V DC Input) - COM-13015 - SparkFun Electronics -...
  2. K

    USA Chattering Contactors

    I am working on a chiller system that runs a hydraulic pump as well as a cooling fan. I was sent out to replace the control board for the system as well as a contactor. I have a transformer running 24VAC to A1 on both the pump contactor and fan contactor as well as a port on my control board...
  3. H

    Problem with contactors wired in parallel

    OK I've got 2 contactors where the coils are wired in parallel. They are sitting right next to each other, One pulls in and holds perfectly well. The other pulls in and drops out. Pulls in again drops out. Ect. Ect. For as long as you are trying to keep the contacts closed. I've tried...
  4. B

    Solar Where to purchase 2 pole DC Contactors suitable for switching 20-25amp 600volt DC PV array preferably with 230volt AC coil.

    I am trying, with little success, to purchase 2 pole DC Contactors suitable for switching 20-25amp 600volt DC preferably with 230volt AC coil. I require these for switching the supply from PV array. If you are able to supply or suggest where I might be able to get them I would be most grateful...
  5. C

    Why are the contactors always closed/energized?

    I just installed a brand new 36 kw electric boiler. 240v, 3 ph, works good, more expensive to operate than I had hoped...regardless when the power/circuit breakers are on, the contactors energize/close always. Why? That makes no sense to me. What’s their purpose if always energized. Why not...
  6. L

    Energize a contactor/relay from multiple toggle (not momentary) switches?

    Is it possible to energize a contactor/relay from multiple toggle (not momentary) switches in a way similar to 3-way switches? If so, what components and setup would do that? The purpose is to control lighting from several sources and the reason for not using simple 3-way switches is that the...
  7. D

    230/250 V Contactors Buzzing/Hot

    Hi. I've got some lighting & cooker contactors buzzing & overheating.. There are a few old ones in situ with visual thermal damage. coil rated at 250V I have new ones that are quiet but still warm to touch the sides. coil rated at 230V I've read that the 230/250 AC coil contactors dont cope...
  8. James

    OLD Contactors available

    not quite sure how to tag someone in, @Lucien Nunes hope that worked? I have 3 contactors and original timer unit. circa. 1975 free to good home. just about to replace them with modern alternatives because the line contactor has developed a short on L2 to L3 when energised. I will remove...
  9. I

    Acb,s mccb,s mcb,s contactors enclosures

    In the middle of stripping out a large mains panel and have loads of stuff for sale if anyone interested all merlin gerin and ellison all in exellent condition too much to list
  10. I

    Industrial Digital control of contactors

    We are trying to control a bunch of 3 phase contactors using an HMI. The contactors' coils are activated by two lines of the 240V 3 phase source (L1 and L2). We are trying to figure out if the relays needed for activating the coils should be rated at 120V or 240V, or if we need another type of...
  11. Mark Whitehouse

    Which Starter Contactor

    Hi all I have a 3 hp single phase motor that only runs when you hold the button and stops when you release it. I am struggling to get my head around which contactor to get for it. Any help would be great.
  12. D

    Anyone use the Hylec DOC contactors and overload relays?

    Type: Hylec-APL | Motor Control Gear | Contactors - & Hylec-APL | Motor Control Gear | Thermal Overload Relays - Got a project coming up where I need to remotely start about 20 pumps so looking at Hylec as...
  13. joel89

    Schneider 115a 3 pole contactors

    brand new without the boxes 115a contactors with 110v coils. 3 for sale I am asking for offers around £150 per contactor these cost £300 when I bought them.
  14. A

    Understanding lighting contactor

    Hi guys, I'm new on here, I'm a level 3 apprentice, most of my experience is commercial and domestic, my boss has just taken on a large industrial job, in which we are testing and rewiring everything, first we are doing the lights, we will be fitting some lighting contacters, which will run...
  15. joel89

    For Sale Schneider 115a contactors

    hi for sale I have 3 x Schneider LC1 115a 3 Pole contactors brand new never used 110v Ac coils. Cost over £250 each I am asking. High spec contractors for the money £125 Ono.
  16. S

    Ceramic bottle fuse holder, sudden short to DIN rail (earth)

    Hello... Anyone had any extended experience with ceramic bottle fuse holders. Shortly after turning on isolator switch there was phase to ground short between one of fuse terminal metallic parts and DIN rail (35A gL/gG fuses have been taken out to test the correct working order of contactors)...
  17. B

    Contactor Fault

    Hi just after a bit of help with a intermentant issue I have with some car park lighting that is controlled by a time clock and 3 contactors. The contactors are sticking in so the lighting is staying on, ive taken off the load for the lights and the CB for the time clock which resets the...
  18. P

    Commercial Switching 6kW load with 7 day programmer

    I need to switch 2No 3kW heaters on using a 7 day heating programmer. Presumably I'll need a contactor to switch that load rather than the heating programmer (?). Can anyone recommend a suitable one? Many thanks if anyone can help, Peter
  19. M

    Places to sell a job lot of contactors

    I have a job lot of contactors I have no idea where to sell. Ebay has very little of the items i am trying to sell. Could do with some details of people who can take on job lots like this. They are mostly Matsu****a contactors used at injection molding plant
  20. joel89

    Contactors and Relays (anti vibration ?)

    I have a panel, on our large hammer forge which causes a hell of a lot of vibration hitting a 5tonne tube, anyway I am loosing my retain on 2 x small contactors LC1 18a which feed a servo and lubrication system and when the tube is nearly forged into a bottle neck shape it also causes a small 5a...
  21. J

    Commercial LED ceiling tiles startup current

    I have been asked to quote a shop fit out that will have 52x 45w LED ceiling tiles overall. they would like 12 switched at a time if possible, but on a previous job I only had 6 on one switch and had to use a 10A C-type MCB just to sto pthem tripping out on startup. I was thinking of wiring...
  22. D

    Fault on BMS

    Hi Guys, I work for a maintenance company and just had a call out to attend tomorrow at a TK Maxx store. The info I have been given is that the store lights are not turning off when the alarm is set by the manager at closing. I know all these stores use building management systems and I just...
  23. B

    Sizing Contactor to control Photovoltaic DC

    I know this is a U.K. site but I'm hoping someone will be able to answer a qn. Recently I saw a that a company was producing a remote disconnect safety system for PV panels mounted on a roof.This is to disconnect the arrays automatically if the mains is disconnected or manually after a storm or...
  24. M

    Car Ramp 3 Phase

    Hi i am currently installing a Vehicle ramp to my garage, i have discovered that the motor is a dual 3 phase motor and can run on 230 volts 3 phase i have rewired the motor to suit. I am using a Yaskawa Ac Drive V1000 inverter to take 240v single phase to 240v three phase, with the unit...
  25. J

    Industrial Should I use a contactor or a relay?

    I have to design a unit which utilizes both 24V and 110V for lighting. We will supply these voltages by using a dual type transformer. The 24V will supply an alarm and heat tracing whereas the 110V will supply a lighting circuit. Should I install a contactor or a relay to protect from under...
  26. A

    Relays and Contactors

    Hey, I don't quite understand Relays and Contactors previously ive worked for a company and if we ever needed a contactor they just said heres a contactor wire it (For example we used contactors for the air conditioning switching) I know how to wire them and that but i dont UNDERSTAND why they...
  27. E

    Where can i find a 100A/63A change over relay/contractor????

    Anyone know where can i find a 100A/63A change over relay/contractor???? hears a little diagram so you know what im after
  28. F

    relay or contactor

    Hello need some advice wiring up electric AGA via honeywell 1 channel timer. need to use low amp to switch higher amp do I need a contactor or a relay? all at 230v want to protect honeywell timer on 3 amp fuse but switch over 16 amp circuit. Any help advise would be good thanks
  29. T

    out of the game for 2yrs....thoughts wanted!!!!

    Hello to all Just wanted your thoughts really,well im an electrician with 10yrsexperience but worried getting back into the mix.Come out of the trade for a while due to personal reasons,ive got my C&G parts 1,2 and 16th edition,due to do my 17th in a couple of weeks. My concern is that i have...
  30. T

    Contactor, Timer Circuit Design HELP!

    I have a question. Basically I have been asked to install electrical heaters in a large area and the customer wants them timed and on thermostatic controls. Which is fine you can just buy the plug in's right? Bloody hell their expensive! I haven't played with contactors and din rail timers...
  31. La Poste

    Contactors vs relays.

    Does anyone know why contactors are more expensive than relays? In my mind they do the same thing in fact relays do more (IE normally on/ normally off terminals) so why the difference in price IE contactors are more expensive, I don't get it. Thanks.
  32. R

    industrial roller shutter door.

    A friend of mine has a 3phase roller door. Under normal circumstances you press the up button and it opens and continues to go up untill the limiter switch kicks in. When it comes down you have to press and hold the down button. I guess this is for safety reasons. The up button has stopped...
  33. D

    Emergency lighting key switch

    Is there any reg on emergency lighting should be on a key switch in bs7671, I know of it coming up in bs5266.
  34. E

    Contactor for lighting and Last Man Out Switch

    Hi, looking for some alternative views on this. Need to fit a contactor and last man out switch for a large house with 2 consumer units, each controlling roughly half of the house. They are fed from 2 separate phases from the 3 phase board. The last man out switch will be by the front door...
  35. S

    Fitting dol contactor for 415 v3 phase fans

    I have to fit dol contactor for 415v 3phase fans where the contactor must switch at 110volt how is this done please.
  36. S

    Question about non-automatic transfer switch

    hi, i want to design non-automatic transfer switch by 2 contactors and push buttons. my question is do i need mechanical between the 2 contactors? or it is enough to work with NO-NC for both contactors. please help me
  37. I

    Anyone much experience with Relays?

    I'm embarrassed to say I know very little about Relays. Never really had much dealings with them. I have a job next week and from the email I got from the company I will have to do the following: 1: Install new speed drives in new enclosure with MCBs ( Either 1 or 2 Drives ) 2: Mount new...
  38. C

    Underfloor Heating Using Contactor(s)

    how do I wire a single phase contactor to underfloor heating? Do I take the load / ie the electrical mat to 2 and 4 and do i take a switch wire to A1 to switch the contactor? and should I locate the contactor(s) next to the consumer unit in a separate box with its own DIN rail? The house is a...
  39. B


    hi there i have got my am2 on tue and am fairly confident with the installation but when it comes to the fault finding do you just use the test procedures out of the on site guide or do you have to use any other methods???? thank you
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