Connect with us

Rewiring a ballast. Help needed.

Discussion in 'Electronic Repair' started by Sean, Mar 12, 2005.

Scroll to continue with content
  1. Sean

    Sean Guest

    Hello, I am having some trouble rewiring a ballast. It's an older one that
    my wife has above her fish tank. The On/Off switch is flaky (it works about
    30% of the time) so she wants to set it up on a timer to go on and off for
    her fish.
    I am trying to bypass the on/off switch, but I am having some trouble as it
    is an older ballast.
    Here's the scoop.
    It is a 4 foot single lamp ballast.
    There is the standard black and white wires, plus a blue wire. (I am used to
    seeing 6 wires in a 2 lamp system.)
    The black goes to the Power. The white goes to the right hand side of the
    lamp. The blue goes to the left hand side. Coming from the left side of the
    lamp is another black that connect to the top left of the on/off switch. The
    top right of the switch goes to the right side of the lamp. The bottom right
    of the switch goes to the other connector on the right side of the lamp. The
    bottom left of the switch goes back to Power.
    I am sorry if this is a little complicated, but that's the best I can do in
    writing.
    I figured that I should connect the black from the left side of the lamp to
    one of the wires on the right side of the lamp, and connect the other wire
    from the right side back to power. That doesn't work. (I get a very low glow
    from half the bulb, but it doesn't go on.)
    Any suggestions would be appreciated.
    Here are the specs on the ballast in case they are needed:
    120V 60hz .55 amp
    Keystone Transformer Co.
    Cat no. M4OP
    40 W Ballast.

    Thanks a lot!
    Sean.
     
  2. Jerry G.

    Jerry G. Guest

    Excellent webpage about fluorescent lamp theory, and how to wire them. There
    are some ASCII type diagrams towards the bottom of the document. The
    diagrams shown, are very standard.

    http://members.misty.com/don/f-lamp.html#int0

    --

    Jerry G.
    ======


    Hello, I am having some trouble rewiring a ballast. It's an older one that
    my wife has above her fish tank. The On/Off switch is flaky (it works about
    30% of the time) so she wants to set it up on a timer to go on and off for
    her fish.
    I am trying to bypass the on/off switch, but I am having some trouble as it
    is an older ballast.
    Here's the scoop.
    It is a 4 foot single lamp ballast.
    There is the standard black and white wires, plus a blue wire. (I am used to
    seeing 6 wires in a 2 lamp system.)
    The black goes to the Power. The white goes to the right hand side of the
    lamp. The blue goes to the left hand side. Coming from the left side of the
    lamp is another black that connect to the top left of the on/off switch. The
    top right of the switch goes to the right side of the lamp. The bottom right
    of the switch goes to the other connector on the right side of the lamp. The
    bottom left of the switch goes back to Power.
    I am sorry if this is a little complicated, but that's the best I can do in
    writing.
    I figured that I should connect the black from the left side of the lamp to
    one of the wires on the right side of the lamp, and connect the other wire
    from the right side back to power. That doesn't work. (I get a very low glow
    from half the bulb, but it doesn't go on.)
    Any suggestions would be appreciated.
    Here are the specs on the ballast in case they are needed:
    120V 60hz .55 amp
    Keystone Transformer Co.
    Cat no. M4OP
    40 W Ballast.

    Thanks a lot!
    Sean.
     
  3. If I understand all this correctly the switch has four connections. Is
    that correct? From your description is seems that this is a Preheat
    (switch start) circuit and you will not be able to replace the
    four-contact switch with a two-contact switch of any type. The switch
    provides the functions of both power switch and starter switch. (It
    must have three positions, even if one is momentary: Off, On, and
    Start.) You could use a standard power switch and then a glow bottle
    starter - if you can find one to match your lamp - but you would be
    better off replacing the ballast with something more modern that can
    be controlled with a simple series switch.

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
  4. NSM

    NSM Guest

    I bet you press and hold the switch, then release it. During the press and
    hold the lamp is shorted out to preheat the filaments. You need the special
    switch. Ask at a hardware store, but make sure the guy knows what he is
    talking about.

    N
     
  5. Sean

    Sean Guest

    Thanks for the reference. The diagrams help a lot.
    Sean.
     
  6. Sean

    Sean Guest

    Thanks for the answer. I was hoping to simply bypass the switch, but it
    doesn't look like that is going to happen. I guess I'll have to replace the
    ballast after all.
    Thanks, Sean
     
  7. James Sweet

    James Sweet Guest

    While it's hard for me to visualize without a drawing, it sounds somewhat
    like a switch start preheat ballast where you turn the switch on and hold it
    for a moment to preheat the cathodes. If that's the case then to bypass it
    you would need to install a starter in place of the starting contacts in the
    power switch.
     
  8. James Sweet

    James Sweet Guest

    You can buy a glowbottle starter at any hardware store, usually under a
    dollar.
     
  9. But it must match his lamp. While the Op did not give us lamp data, he
    indicated it was a 40-watt ballast. Therefore I am assuming the lamp
    is a 40-watt or 34-watt lamp (until I get better information.) If the
    OP lives in the US, I do not believe he can purchase a glow starter
    for 40-watt lamps since they will not operate from 120 volt power
    supplies. if the OP lives in a part of the work where the normal
    supply voltage is 220 to 240 volts, he should be able to find a glow
    starter.

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
  10. James Sweet

    James Sweet Guest

    40W glowbottle starters are readily available in the US, they were widely
    used up until the 70's when rapid start came out and there's still quite a
    few old fixtures that use them. I have a 4 lamp 4' preheat fixture from the
    60's that uses 120v autotransformer ballasts and glowbottle starters.

    I have found also that starters are quite non critical, and I've used a 20W
    starter in a pinch, though it likely wouldn't last as long.
     
  11. Dan

    Dan Guest

    I appreciate your desire to get this to work & the fun/challenge
    therein, but should it prove to be more f'ing around than it's worth,
    keep in mind you can buy a brand new 4' single tube starterless light
    for $10-15. They usually come "knocked down", so it would be a pretty
    easy task to fit the new ballast etc to the existing fixture/fish tank,
    should you not be able to use the entire new fixture itself.

    Dan
     
  12. Actually rapid start is much older than the 1970's, but you are
    correct about 40-watt preheat start lamps. The 1981 IES Handbook lists
    both 40-watt T12 and 90-watt T17 preheat start lamps. Thanks - I
    learned something new today.

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
  13. James Sweet

    James Sweet Guest

    Perhaps it was 60's? I'm not sure really, but I do know that preheat start
    40W tubes were very common in the 50's and at least partly into the 60's, RS
    didn't seem to catch on until the 70's. One possible reason is that RS has
    much more trouble starting in cold weather or high humidity and requires a
    grounded reflector in close proximity to the lamp.

    The 90W T17 lamps are dinosaurs, I've never actually seen one up close but
    they were used in streetlighting some in the 50's. Another neat lamp I'd
    love to get my hands on are the GE PowerGroove PG17 series of VHO (1500mA)
    lamps that were somewhat common in the 70's. They use a rippled tube that
    allows a 9' arc length in an 8' tube and were available in 4' as well.
     
  14. NSM

    NSM Guest

    Add a glow lamp starter to the circuit. That should work fine with the
    existing ballast. Otherwise you'll need a complete new ballast, and a
    complete new lamp is cheaper. In Canada you can get models with an
    electronic ballast quite cheap. Home Depot or Rona will have these -
    possibly on sale. They plug in, so you can plug it into a wall timer. Easy,
    cheap!

    N
     
  15. We need some input from Terry here, but we developed the 34-watt T12
    energy saving lamp while I was working at GE Lighting in the
    mid-1970's. One problem with the lamp was that due to the lower lamp
    voltage the 34-watt lamp placed more voltage stress on the internal
    capacitor in rapid start ballasts. When the new 34-watt lamp was
    installed in fixtures with old rapid start ballasts, many of the
    capacitors, which were near end of life anyway, blew. So these
    ballasts must have been almost 20 years old by 1975- which means they
    were popular by the mid-1950s. By the mid-1970's the 40-watt rapid
    start lamp was nearing the end of its life due to the new 34-watt
    rapid start lamp.
    Well, we had lots of Power Groove lamps at Nela Park along with its
    inventor - who I believe was Gene Lemmers - who also co-invented the
    rapid start ballast, I believe with John Aicher. Terry, can you help
    here? The Power Groove lamp was introduced by GE about 1956 and was a
    rapid start lamp, so the basic rapid start system must be older than
    that.

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
  16. James Sweet

    James Sweet Guest

    Those 34W lamps were (and are) awful, always dim and they flicker if it's
    even a bit chilly. I always thought it was so silly that with the
    regulations for efficiency of the lamps and ballasts the end result was that
    we had more efficient but dim lamps so you had to use more of them resulting
    in a net increase in ballast losses and overall power.
    I didn't realize the PG's came out so long ago. HO and VHO have always been
    RS as far as I know, for some reason it took longer for RS to catch on for
    indoor use though, I'm not really sure why. You don't see many PG lamps
    anymore, I think only the 96" version is still in production. VHO in general
    is not real popular these days, I have a couple 4' VHO fixtures in my
    garage, they're very bright but not real efficient and the phosphor is hit
    so hard with UV that it degrades fairly rapidly. It'd probably work well
    using a modern trichromatic phosphor but as far as I know nobody makes
    those.
     
  17. Sean

    Sean Guest

    I'll try and locate a glow bottle. I live in a small town in Canada, and
    there is not a lot of selection in some of the local stores. I'll try Radio
    Shack and the local lumberyard, but I am not holding my breath. I'll have to
    wait until I can get down to the "Big City" and see if I can locate one
    there.
    How would I wire the glow bottle into the circuit that I described? (With
    the intention that the light is "always" in On mode. The timer will be
    taking care of turning it on and off.)
    Thanks, Sean
     
  18. Someone else gave you a link to Don's lighting site. Look and the
    second diagram under preheat start. That being said, you need more
    information than you provided in your original note.

    You will see from Don's diagram and perhaps your own experience, that
    each end of the lamp has two pins. You have told us in your original
    note that a certain wire goes to a certain end of the lamp, but NOT TO
    WHICH PIN, which is critical.

    Based on what you wrote, I THINK that the starter would wired to the
    two wires that go respectively to the top left and top right contact
    of your switch. But this is ONLY correct if the wire currently
    connected to the top right hand contact of the switch is also
    connected to the pin on the right side of the lamp that does NOT also
    connect to the power line. I assume that the white lead from the
    ballast goes to the SAME lamp pin as the power line, so there are two
    wires connected to this AND ONLY THIS lamp pin.

    If my assumptions about which wires go to which lamp pins are not
    correct, then the rest of my suggestions should be ignored.

    If the above is correct, then the timer switch is wired between the
    two bottom contacts of the switch.

    The information above is provided for educational purposes and you are
    responsible for understanding the hazards of working with electrical
    circuits and any damage to person or property that may result from
    experimenting with this lamp circuit.

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
  19. Actually, they are my diagrams. :)
    Huh? Unless I misunderstand your statement, it is irrelevant.

    --- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
    Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
    +Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
    | Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

    Note: These links are hopefully temporary until we can sort out the excessive
    traffic on Repairfaq.org.

    Important: Anything sent to the email address in the message header above is
    ignored unless my full name is included in the subject line. Or, you can
    contact me via the Feedback Form in the FAQs.
     
  20. I apologize for the error.
    The OP has described 5 wires going to a 4-pin lamp - so (at least) one
    lamp pin must have two wires. One of those 5 wires goes directly to
    the power line. He must not connect the starter to the lamp pin that
    is connected to the power line. As you know, the starter is to be
    connected from one end of the lamp to the other, and connected to the
    side of each electrodes that is not connected to the ballast or power
    line per _your_ diagram :)

    --
    Vic Roberts
    http://www.RobertsResearchInc.com
    To reply via e-mail:
    replace xxx with vdr in the Reply to: address
    or use e-mail address listed at the Web site.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-