A VAX 6600 room fan - DEC

This is a discussion on A VAX 6600 room fan - DEC ; I posted this on comp.os.vms, but then remembered I've inquired of this group before and received some great guidance - thanks to all of you who've helped. But I still don't have my VAX 6600 running. The basic symptom has ...

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Thread: A VAX 6600 room fan

  1. A VAX 6600 room fan

    I posted this on comp.os.vms, but then remembered I've inquired of this
    group before and received some great guidance - thanks to all of you
    who've helped. But I still don't have my VAX 6600 running. The basic
    symptom has not changed: I turn on the machine, hear the 'clunk' of the
    relay, fans come on, lights come on for five seconds or so - then they
    go off. Fans stay running. LEDs on the front of the H7206B show the
    two greens glowing happily, but also the red LED that says, "XMI-1 card
    in XMI-2 cage" (which is not the case, and the LED is lit even with NO
    cards in the cage). I've replaced the H7206B, the XTC sequencer and the
    cable from the 7206B to the regulators.

    I noticed that most of the regulators come on briefly (i.e. their green
    LEDs come on, then extinguish), except for the XMI-side H7215. So I
    swapped the XMI-side regulator for the BI-side regulator. Same story:
    the XMI-side H7215 does not fire up.

    While troubleshooting this, I noticed a couple of odd things. If I
    remove the control cable from J2 on the XMI H7215, the front panel LEDs
    don't extinguish after five seconds and the other regulators continue to
    show DC OK (but of course, the machine won't boot because it's missing
    several essential voltages). The other odd thing: no matter what, the
    fan in the H7206B doesn't turn. Sure, it could be bad - but I tested
    the fan in the original 7206B (which demonstrated the same symptom) and
    it's just fine. It *looks like* the 24v for this fan comes off the same
    pads as connect to J2, which runs the big cabinet fans (which run fine -
    I really checked that they're getting power), but that fan does not turn.

    Yes, I checked both the temp sensor and the airflow sensor (on top of
    the XMI cage), and they do not show defects. I've double checked all
    the cables and connections, including all those weird little sense lines
    and interlocks; yes, the card cage covers are in place (and the
    interlock switches test good). The XMI H7215 has 300v going into its
    front side.

    Does this weird set of new symptoms/behaviors sound familiar to anyone?
    This is an awfully big room fan.... Also, does anyone know where I
    can find any diagrams? I've reviewed the platform owner's manual,
    service manual and technical user's guide, but nothing gives even pinouts.

    Thanks -- Ian

    iking (at-thing) killthewabbit (dot-thing) org

  2. Re: A VAX 6600 room fan

    Ian King wrote:
    > I posted this on comp.os.vms, but then remembered I've inquired of this
    > group before and received some great guidance - thanks to all of you
    > who've helped. But I still don't have my VAX 6600 running. The basic
    > symptom has not changed: I turn on the machine, hear the 'clunk' of the
    > relay, fans come on, lights come on for five seconds or so - then they
    > go off. Fans stay running. LEDs on the front of the H7206B show the
    > two greens glowing happily, but also the red LED that says, "XMI-1 card
    > in XMI-2 cage" (which is not the case, and the LED is lit even with NO
    > cards in the cage). I've replaced the H7206B, the XTC sequencer and the
    > cable from the 7206B to the regulators.


    I have Vax 6000 systems - one at work, one at home, but they are
    6300/6400 systems and they don't have all the same voltages the 6500 and
    6600 series have. That said it sounds like a protective shutdown of
    some kind, due to either under or over voltage. The other possibility
    would be ovecurrent, but I would have thought it would be more obvious
    if that was the case.

    > I noticed that most of the regulators come on briefly (i.e. their green
    > LEDs come on, then extinguish), except for the XMI-side H7215. So I
    > swapped the XMI-side regulator for the BI-side regulator. Same story:
    > the XMI-side H7215 does not fire up.


    This still happen with all the card cages unpopulated? Something faulty
    in the cage pulling one of the supply rails down?

    > While troubleshooting this, I noticed a couple of odd things. If I
    > remove the control cable from J2 on the XMI H7215, the front panel LEDs
    > don't extinguish after five seconds and the other regulators continue to
    > show DC OK (but of course, the machine won't boot because it's missing
    > several essential voltages).


    Definitely sounds like a voltage that is wrong or perhaps a downstream
    regulator/supply that has died.

    > The other odd thing: no matter what, the
    > fan in the H7206B doesn't turn. Sure, it could be bad - but I tested
    > the fan in the original 7206B (which demonstrated the same symptom) and
    > it's just fine. It *looks like* the 24v for this fan comes off the same
    > pads as connect to J2, which runs the big cabinet fans (which run fine -
    > I really checked that they're getting power), but that fan does not turn.


    Are they temperature controlled? Only cut in when needed?

    > Yes, I checked both the temp sensor and the airflow sensor (on top of
    > the XMI cage), and they do not show defects. I've double checked all
    > the cables and connections, including all those weird little sense lines
    > and interlocks; yes, the card cage covers are in place (and the
    > interlock switches test good). The XMI H7215 has 300v going into its
    > front side.


    I think you need to find what all the voltages are supposed to be, then
    start measuring them with a good DVM and see if there is one or more
    that is significantly over or under what it should be.

    > Does this weird set of new symptoms/behaviors sound familiar to anyone?
    > This is an awfully big room fan....


    They make better room *heaters*....

    > Also, does anyone know where I can
    > find any diagrams? I've reviewed the platform owner's manual, service
    > manual and technical user's guide, but nothing gives even pinouts.


    I've never seen diagrams for them, but possibly someone else in the
    group might be able to help. I'll have a look at what I have, but
    not sure how useful it will be.


    --
    The CO

  3. Re: A VAX 6600 room fan

    The CO wrote:
    > Ian King wrote:
    > > I posted this on comp.os.vms, but then remembered I've inquired of this
    > > group before and received some great guidance - thanks to all of you
    > > who've helped. But I still don't have my VAX 6600 running. The basic
    > > symptom has not changed: I turn on the machine, hear the 'clunk' of the
    > > relay, fans come on, lights come on for five seconds or so - then they
    > > go off. Fans stay running. LEDs on the front of the H7206B show the
    > > two greens glowing happily, but also the red LED that says, "XMI-1 card
    > > in XMI-2 cage" (which is not the case, and the LED is lit even with NO
    > > cards in the cage). I've replaced the H7206B, the XTC sequencer and the
    > > cable from the 7206B to the regulators.

    >
    > I have Vax 6000 systems - one at work, one at home, but they are
    > 6300/6400 systems and they don't have all the same voltages the 6500 and
    > 6600 series have. That said it sounds like a protective shutdown of
    > some kind, due to either under or over voltage. The other possibility
    > would be ovecurrent, but I would have thought it would be more obvious
    > if that was the case.
    >
    > > I noticed that most of the regulators come on briefly (i.e. their green
    > > LEDs come on, then extinguish), except for the XMI-side H7215. So I
    > > swapped the XMI-side regulator for the BI-side regulator. Same story:
    > > the XMI-side H7215 does not fire up.


    The voltages for the H7215 ( -5, -2, +-12), using a scope,
    do they come on briefly or can you isolate or take the loads of them ?

    >
    > This still happen with all the card cages unpopulated? Something faulty
    > in the cage pulling one of the supply rails down?
    >
    > > While troubleshooting this, I noticed a couple of odd things. If I
    > > remove the control cable from J2 on the XMI H7215, the front panel LEDs
    > > don't extinguish after five seconds and the other regulators continue to
    > > show DC OK (but of course, the machine won't boot because it's missing
    > > several essential voltages).

    >
    > Definitely sounds like a voltage that is wrong or perhaps a downstream
    > regulator/supply that has died.
    >
    > > The other odd thing: no matter what, the
    > > fan in the H7206B doesn't turn. Sure, it could be bad - but I tested
    > > the fan in the original 7206B (which demonstrated the same symptom) and
    > > it's just fine. It *looks like* the 24v for this fan comes off the same
    > > pads as connect to J2, which runs the big cabinet fans (which run fine -
    > > I really checked that they're getting power), but that fan does not turn.

    >
    > Are they temperature controlled? Only cut in when needed?
    >
    > > Yes, I checked both the temp sensor and the airflow sensor (on top of
    > > the XMI cage), and they do not show defects. I've double checked all
    > > the cables and connections, including all those weird little sense lines
    > > and interlocks; yes, the card cage covers are in place (and the
    > > interlock switches test good). The XMI H7215 has 300v going into its
    > > front side.

    >
    > I think you need to find what all the voltages are supposed to be, then
    > start measuring them with a good DVM and see if there is one or more
    > that is significantly over or under what it should be.
    >
    > > Does this weird set of new symptoms/behaviors sound familiar to anyone?
    > > This is an awfully big room fan....

    >
    > They make better room *heaters*....
    >
    > > Also, does anyone know where I can
    > > find any diagrams? I've reviewed the platform owner's manual, service
    > > manual and technical user's guide, but nothing gives even pinouts.

    >
    > I've never seen diagrams for them, but possibly someone else in the
    > group might be able to help. I'll have a look at what I have, but
    > not sure how useful it will be.
    >
    >
    > --
    > The CO



  4. Re: A VAX 6600 room fan

    bob.birch@gmail.com wrote:

    > The voltages for the H7215 ( -5, -2, +-12), using a scope,
    > do they come on briefly or can you isolate or take the loads of them ?


    I'll have a look. Not sure off hand. I've never had any significant
    issues with a 6000 system, the most work done on the psu was to make the
    system run from 240v single phase instead of 415v 3 phase.

    --
    The CO

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