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
...

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

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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 kilowatthour 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.

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 kilowatthour on your utility bill.
> The rest is simple arithmetic..
>
I hear this all the time when I tell people I have PDP11'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 3way 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 PDP11'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  democracy (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

Re: Power requirements?
Hi Julian:
These are quiescent wattage consumptions. Start up of drives with
motors in them consume approximately 67 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 ~ 1617 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
> infopdp11request@village.org, with the first line of the message
> body being "unsubscribe" or "subscribe", respectively (without the quotes).

Re: Power requirements?
Apologie.....I spoke in error wrt the ampacities cited below. Thank you
Tom for pointing this out. I misremembered 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 67 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 ~ 1617 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
>> infopdp11request@village.org, with the first line of the message
>> body being "unsubscribe" or "subscribe", respectively (without the
>> quotes).