Power requirements? - VMS

This is a discussion on Power requirements? - VMS ; Can anyone give ballpark power requirements for the following components? Ok, looking at the specs on each unit, I was able to discern the following: An RX01 takes 100 watts to run. A PDP 11/04 takes 110 watts to run ...

+ Reply to Thread
Results 1 to 5 of 5

Thread: Power requirements?

  1. Power requirements?

    Can anyone give ballpark power requirements for the following components?

    Ok, looking at the specs on each unit, I was able to discern the following:

    An RX01 takes 100 watts to run.

    A PDP 11/04 takes 110 watts to run

    An RK05 takes 178 watts to run

    Does this really add up to 388 watts or is there something I'm missing?

    Also, running these devices all the time, what would that look like on a power bill?

    Thanks!

    Julian




    ----------
    To unsubscribe (or subscribe) from (to) this list, send a message to
    info-pdp11-request@village.org, with the first line of the message
    body being "unsubscribe" or "subscribe", respectively (without the quotes).

  2. Re: Power requirements?

    Julian Wolfe (FireflyST) wrote:
    > An RK05 takes 178 watts to run


    Probably more while it is actively seeking, also when
    coming up to speed after loading a cartridge.

    > Also, running these devices all the time, what would that look like on a power bill?


    Check the cost per kilowatt-hour on your utility bill.
    The rest is simple arithmetic..

    I should warn you not to leave antique electromechanical
    stuff running unattended very much, because there are
    many things that can go wrong (more likely now than
    originally) and it can produce a big mess is an operator
    is not around to shut it down at the first funny sound.


  3. Re: Power requirements?

    In article ,
    "Douglas A. Gwyn" writes:
    > Julian Wolfe (FireflyST) wrote:
    >
    >> Also, running these devices all the time, what would that look like on a power bill?

    >
    > Check the cost per kilowatt-hour on your utility bill.
    > The rest is simple arithmetic..
    >


    I hear this all the time when I tell people I have PDP-11's and Vaxen
    running at my house. They obviously don't have a wife or kids.

    Bedroom lights - (4) 60 watt bulbs - 240 watts
    Living room lights - 2 3-way lamps 110 watts each - 220 watts
    Backyard spotlights 4 340 watt bulbs - 1360 watts

    The last one id often turned on by my wife when she lets the dog
    out int he yard at night and then left on for days at a time. I
    never really understood this as I don't think the dog reads when
    she goes to the bathroom.

    And we won't even go into the curling iron left on (it's bad enough
    that it seems to take more than an hour to reach usable temperature).
    Or the fridge. Or the electric clothes dryer. Or the electric stove
    (I have found the oven left on hours after dinner is finished).

    But, there you have it. My PDP-11's and Vaxen aren't even blips on
    the radar compared to the other stuff in my house. Which is probably
    why my wife has never questioned it. She probably doesn't even notice
    when they are running or not. :-)

    bill

    --
    Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
    bill@cs.scranton.edu | and a sheep voting on what's for dinner.
    University of Scranton |
    Scranton, Pennsylvania | #include

  4. Re: Power requirements?

    Hi Julian:

    These are quiescent wattage consumptions. Start up of drives with
    motors in them consume approximately 6-7 times the quiescent current.
    SPecifically, for example, an RK05 at ~180 watts/120 volts = 1.2 amps *
    6 = ~7.2 amps. In many cases, the startup transient will continue long
    enough to cause the thermal breakers in a house fuse box to open.
    *Typical* house wiring capacity is 20 amps (14 gauge wire), protected by
    breakers that will open at ~ 16-17 amps (according to electrical code
    standards). So, an 11/04 with two RK05s (2*7.2 amps + 1 amp of CPU
    load) = ~16 amps.....you will be on the cusp of the protection.
    Probably will work though. One solution would be to spin up each drive
    separately.
    I just took the wattage numbers you gave me...You would be wise to
    consult the PDP 11/xx handbook to look up the actual loads and do the
    math exemplified above.
    How would it affect the power bill? That can be easily calculated.
    Look at your electrical bill for the cost per killowatt hour ($/KWH).
    Compute how many watts you will be consuming over how many hours and
    multiply it times the $/KWH figure. This will give a pretty good
    ballpark.
    ALso factor into consideration cooling loads - if in the summer you will
    be running an air conditioner to remove heat generated by the system,
    you will need to add that wattage usage (basically 1BTU - 776 watts if I
    recall correctly).
    Running the system in the winter can help offset heating costs A
    great justification for getting a dec system 10, lol.
    John


    Julian Wolfe (FireflyST) wrote:
    > Can anyone give ballpark power requirements for the following components?
    >
    > Ok, looking at the specs on each unit, I was able to discern the following:
    >
    > An RX01 takes 100 watts to run.
    >
    > A PDP 11/04 takes 110 watts to run
    >
    > An RK05 takes 178 watts to run
    >
    > Does this really add up to 388 watts or is there something I'm missing?
    >
    > Also, running these devices all the time, what would that look like on a power bill?
    >
    > Thanks!
    >
    > Julian
    >
    >
    >
    >
    > ----------
    > To unsubscribe (or subscribe) from (to) this list, send a message to
    > info-pdp11-request@village.org, with the first line of the message
    > body being "unsubscribe" or "subscribe", respectively (without the quotes).


  5. Re: Power requirements?

    Apologie.....I spoke in error wrt the ampacities cited below. Thank you
    Tom for pointing this out. I mis-remembered the tables from the NEC.
    Specifically, According to the NEC (1990), Allowable Ampacities of
    Insulated Copper Conductors @ 30 degrees C, (86 degrees F), single
    conductor in free air....(14 AWG, 20 amps @ 60 degrees C) and (12 AWG,
    25 amps @ 60 degrees C).... Which is what I said below...*however,* a
    single conductor is not the case in house wiring.....It should have been:
    Allowable Ampacities of Insulated Copper Conductors @ 30 degrees C, (86
    degrees F), not more than three conductors in a raceway, or cable or
    direct burial, based on room temp of 30 degrees C.....(14 AWG, 15 amps @
    60 degrees C) and (12 AWG, 20 amps @ 60 degrees C). Clearly this is the
    case in most house wiring (i.e. romex run through 2x4 and thin wall
    conduit).
    So, the bottom line is (going strictly by the numbers), 14 AWG would not
    be sufficient because most likely the breakers would open during the
    transient startup conditions. To be properly protected according to
    code, you would have to use a circuit composed of 12 AWG, protected by a
    20 amp breaker.

    John

    John Hudak wrote:
    > Hi Julian:
    >
    > These are quiescent wattage consumptions. Start up of drives with
    > motors in them consume approximately 6-7 times the quiescent current.
    > SPecifically, for example, an RK05 at ~180 watts/120 volts = 1.2 amps *
    > 6 = ~7.2 amps. In many cases, the startup transient will continue long
    > enough to cause the thermal breakers in a house fuse box to open.
    > *Typical* house wiring capacity is 20 amps (14 gauge wire), protected by
    > breakers that will open at ~ 16-17 amps (according to electrical code
    > standards). So, an 11/04 with two RK05s (2*7.2 amps + 1 amp of CPU
    > load) = ~16 amps.....you will be on the cusp of the protection. Probably
    > will work though. One solution would be to spin up each drive separately.
    > I just took the wattage numbers you gave me...You would be wise to
    > consult the PDP 11/xx handbook to look up the actual loads and do the
    > math exemplified above.
    > How would it affect the power bill? That can be easily calculated.
    > Look at your electrical bill for the cost per killowatt hour ($/KWH).
    > Compute how many watts you will be consuming over how many hours and
    > multiply it times the $/KWH figure. This will give a pretty good ballpark.
    > ALso factor into consideration cooling loads - if in the summer you will
    > be running an air conditioner to remove heat generated by the system,
    > you will need to add that wattage usage (basically 1BTU - 776 watts if I
    > recall correctly).
    > Running the system in the winter can help offset heating costs A
    > great justification for getting a dec system 10, lol.
    > John
    >
    >
    > Julian Wolfe (FireflyST) wrote:
    >
    >> Can anyone give ballpark power requirements for the following components?
    >>
    >> Ok, looking at the specs on each unit, I was able to discern the
    >> following:
    >>
    >> An RX01 takes 100 watts to run.
    >>
    >> A PDP 11/04 takes 110 watts to run
    >>
    >> An RK05 takes 178 watts to run
    >>
    >> Does this really add up to 388 watts or is there something I'm missing?
    >>
    >> Also, running these devices all the time, what would that look like on
    >> a power bill?
    >>
    >> Thanks!
    >>
    >> Julian
    >>
    >>
    >>
    >>
    >> ----------
    >> To unsubscribe (or subscribe) from (to) this list, send a message to
    >> info-pdp11-request@village.org, with the first line of the message
    >> body being "unsubscribe" or "subscribe", respectively (without the
    >> quotes).


+ Reply to Thread