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Power consumption of network printer?

Power consumption of network printer?

Power consumption of network printer?

(OP)
For an HP network printer (your average firm's small laser printer), what VA rating would you use?  We actually hooked up a power meter and found that it took about .3A in standby mode, but while processing a job it varied between 3 and 8 amps.  My supervisor came to the conclusion that the NEC is appropriate to use in this case (180VA for General Purpose receptacles).  This conclusion was based mainly on the fact that the high current draw doesn't last long.  I am not quick to accept this and I would like some more opinions.  thanks!

Nathan (s0naharn@yahoo.com)

RE: Power consumption of network printer?

hi nathanh
  ok I can't find a manual for a hp lj series but if grab the manual there WILL BE a set of electrical specs in it. These will give you the "rated current or load" this will be the value to use whe considering wiring loading.If not hit HPs web site- they will tell you.
Bear in mind these days it seems every thing is energy compliant ( what ever happened to the off switch?) and the stand by mode current is not the load your cables will see when its working. The manufacturer will allow for a typical duty cycle (whilst its doing a print) and that should comply with your standards.
 ps my ink jet is rated at about 15W


an interesting by-line is that a recent survey down here in Aus showed that 30% yes 30% of power consumed in a domestic home was from stand by appliances !!!!

Let us know how it goes
Don

RE: Power consumption of network printer?

Suggestion: When it comes to intermittent loads, one must notice how many intermittent loads are on the circuit and try to see their load profiles with respect of time. In some cases, the intermittent loads are suitable accommodate on relatively small power supplies, and relatively small power strips, 15A.

RE: Power consumption of network printer?

(OP)
Funny thing is I can't find any detailed electrical specs on HP's website, which I thought was odd.  Another note is that we normally put network printers on their own branch circuit.  
Don01, that is interesting about 30% of power consumed is from standby appliances.  
Let's say you had a very large firm with 25 of these printers.  Let's say I used the 8A rating, which would equal 960VA.  Or my supervisors 180VA.  That is a dramatic difference when you multiply by 25 of these.  This could turn out to have a pretty large impact on your feeder size, but in actuality what percentage of the time is the thing in standby mode?  80%?  That is the delima that I face....  I think this is typically why all jobs done per NEC, after it all said an done the peak load is about 40% of capacity.  

Nathan (s0naharn@yahoo.com)

RE: Power consumption of network printer?

in steady state it can be 180 VA but in transient it can demand mor than for times bigger power for a little time (3-10 sec)

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