[volt-nuts] 732A and Prologix received

Randy Evans randyevans2688 at gmail.com
Sun Aug 24 20:01:04 EDT 2014


Bill,

Thanks for the MATH overview.  That could be very helpful.  I definately
will give it a try.

Randy


On Sun, Aug 24, 2014 at 2:44 PM, Bill Gold <wpgold3637 at att.net> wrote:

> Todd:
>
>     I check the batteries every month per the 732A manual.  Usually I keep
> a
> few used cells from previous packs around that seem to be ok after checking
> them for capacity just like checking the battery pack.  I can usually spot
> cells going bad with that method.  If I don't have a spare set then I just
> substitute a used cell until I receive a new set.
>
>     I agree with you that the cheap ones are crap.  I have used Power Sonic
> a lot with some a few EaglePicher and one set of Enersys.  The EaglePicher
> are crap so I will never use them.  EaglePicher have had a couple out of 8
> that have failed very early.  I have never tried Panasonic.  So I stick
> with
> the Power Sonic's.  I am not sure why the 12 volt ones would be better than
> the 6 volts because 12 volt is just 6 lead acid cells while the 6volt are 3
> lead acid cells.  If one of the 6 cells in the 12 volt battery go bad then
> the whole battery has to be changed.  So you better buy good quality 12
> volt
> batteries.
>
>     I just can't seem to source batteries locally easily at a reasonable
> price.  So I order them from Allied usually.
>
> Bill
>
> ----- Original Message -----
> From: "Todd Micallef" <tmicallef at gmail.com>
> To: "Discussion of precise voltage measurement" <volt-nuts at febo.com>
> Sent: Sunday, August 24, 2014 8:13 AM
> Subject: Re: [volt-nuts] 732A and Prologix received
>
>
> > Bill,
> >
> > I use a lot of the 12v 7ah batteries for my UPS backups and 732B. But
> yes,
> > I was mistaken. The 12V 5ah batteries are the ones that I am using in one
> > of my 732A. There is more play inside the tray with the 12v batteries by
> > several mm as compared to the 6v which only has a 2-3mm. The 12v
> conversion
> > is not difficult, but it is easier if the battery tray has already been
> > machined for the 12v batteries. The battery tabs don't line up well with
> > the existing holes and need to be widened. Two additional holes must also
> > be added.
> >
> > Sourcing the batteries locally is more of a convenience than waiting for
> > the delivery. The el-cheapo 6v batteries are a waste of money and I have
> 8
> > batteries so far to prove it. They died the first time I had a 6hr outage
> > and would not hold a charge after that.
> >
> > Todd
> >
> >
> >
> >
> > On Sat, Aug 23, 2014 at 1:21 PM, Bill Gold <wpgold3637 at att.net> wrote:
> >
> > > Randy:
> > >
> > >     I get 6 volt 4 amp/hr (or 4.5 amp/hr) batteries and they will fit
> > > perfect.  Power Sonic PS-640, Genesis NP4-6, Panasonic LC-R064R5C and
> > > others
> > > that are in this size and package.  Order from one of the usual
> electronics
> > > distributors like Allied, Mouser, Digikey.  This is a very common
> battery
> > > as
> > > it is used in a lot of "EXIT" signs so they are lighted when the power
> goes
> > > out.  I don't see how the 12V 7AH will fit as they are too large.  I
> guess
> > > you could use a 12V 5AH (PS1250) as it is the same size as 2 x 6 volt 4
> AH
> > > but the terminals are in the wrong place so you will have to "nibble"
> out
> > > the aluminum plate that holds them in the 732A battery pack.  You have
> to
> > > be
> > > careful if you use the 12v 5AH as you will have 4 extra battery
> connection
> > > leads to deal with and connect correctly.  I would stick with the 6V
> 4AH.
> > > New batteries will last around 12 to 14 hours before the "CAL" light
> goes
> > > out when AC power is not applied.  So shipping to Cal Lab can be a
> problem
> > > if it is a distance away, or you have to use a shipper like UPS or
> FEDEX
> > > and
> > > you ship the night before and then use their "Morning delivery" and the
> Cal
> > > Lab is expecting your 732A.  Same on the way back to you.  Of course
> you
> > > could always strap another battery on the 732A and hook it up to the
> "ext
> > > power" plug to last longer.  I have seen it done.  The issue is to get
> the
> > > Cal Lab to charge the extra battery before they ship the 732A back to
> you.
> > >
> > >     When you remove and work on the battery pack always have the AC
> power
> > > plugged in.  The "CAL" led will stay on because the 18.6 v regulated
> supply
> > > is working.
> > >
> > >     The "CAL" light is to indicate that power has not been lost to the
> > > Reference Amp or other associated circuits.  When the raw supply
> (battery)
> > > voltage drops below about 21 volts the "CAL" light will go out.  Below
> that
> > > voltage the heater circuits will not work correctly and the 18.6 volt
> > > regulated supply will not regulate.  The requirement is that the
> Reference
> > > Amp be kept "alive" at all times to maintain the output voltage that
> was
> > > measured at the time of the most recent Calibration or Certification.
> When
> > > the semiconductor junctions are unbiased and cool off when power is
> lost,
> > > and then power is restored the result will be a different 10 volts than
> > > before the power failure.  My experience is that after all of the years
> > > that
> > > these units have been powered up, this won't happen and when power is
> lost
> > > and then restored, even months later, the 732A will come back to almost
> > > exactly the same 10 volts as when they lost power, usually with in 0.2
> PPM
> > > after 24 hours of "warm up".
> > >
> > >     What type of hookup leads are you using when measuring the 1 volt
> > > output?  What is the PLC set to?  I always use 100 PLC to measure this.
> If
> > > you don't have "low thermal" connection leads you can experience uV
> changes
> > > for a minute or more after plugging in the leads due to the "thermals"
> > > generated because of the difference in temperature between the banana
> jacks
> > > on the 732A and the banana plugs of the leads.  I have found that even
> just
> > > plugging in the lead will generate a thermal difference because of
> > > difference of temps and some heating due to the physical act of just
> > > inserting the plug because of friction between the jack and plug (my
> theory
> > > at any rate).  You have to allow at least a minute or more before being
> > > able
> > > to make a measurement after plugging in the leads.  I just measured the
> > > variation of the 1 volt output of my 732A and using my 3458A and I got
> a
> > > total difference of  0.159 uV over 40 measurements using 100 PLC on the
> 1
> > > volt range of the 3458A.  Using the MATH function and all of the data
> you
> > > can collect.  That was after waiting for several minutes after plugging
> in
> > > the leads.
> > >
> > >     I hope all of this helps.
> > >
> > > Bill
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "Randy Evans" <randyevans2688 at gmail.com>
> > > To: "Discussion of precise voltage measurement" <volt-nuts at febo.com>
> > > Sent: Friday, August 22, 2014 9:03 PM
> > > Subject: Re: [volt-nuts] 732A and Prologix received
> > >
> > >
> > > > Todd,
> > > >
> > > > Thanks for the info.  I have several Panasonic 12V 7 AH batteries
> that
> I
> > > > keep topped off and they have very low current draw (~2 to 3 mA at
> 13.5
> > > > VDC) when charged and at their float voltage, so I am pretty sure
> they
> > > are
> > > > in good condition.  I will look at getting those in the units after I
> > > > ascertain the condition of the 732.
> > > >
> > > > So now I have a what appears to be a functioning 3458A and a 732A but
> > > they
> > > > slightly disagree.  I am like the man with two watches that disagree
> on
> > > the
> > > > time  - which is correct?  For the moment, i am only concerned with
> > > > stability.  The need for absolute accuracy will come later.
> > > >
> > > > Randy
> > > >
> > > >
> > > > On Fri, Aug 22, 2014 at 8:06 PM, Todd Micallef <tmicallef at gmail.com>
> > > wrote:
> > > >
> > > > > Randy,
> > > > >
> > > > > You have two possible choices. It can be configured with 4 x 6v 4Ah
> > > > > batteries or 2 x 12v 7Ah batteries. Hopefully the previous owner
> has
> > > > > modified the battery pack already. A couple of mine needed a
> nibbler
> > > tool
> > > > > to remove enough of the aluminum cover that fits over the tops of
> the
> > > > > batteries. The original cover will short out to the battery tabs
> > > regardless
> > > > > of the battery configuration if this is not done.
> > > > >
> > > > > You can find larger capacity batteries that will give you slightly
> more
> > > > > battery life. I lost a couple sets of mail-order batteries after a
> few
> > > > > extended outages. I would recommend going with locally bought
> batteries
> > > > > instead of the cheaper mail order. My local Batteries Plus will
> > > typically
> > > > > have some warranty if I remember correctly. Moving forward I will
> only
> > > use
> > > > > 2 12v batteries and pre-charge them on a battery charger to
> equalize
> > > them
> > > > > before putting them in the 732A. I think the cheap batteries did
> not
> > > > > discharge equally, and would not recover when power was applied.
> > > > >
> > > > > Inspect the back plane for damaged traces and look at the
> capacitors. I
> > > had
> > > > > a few that looked questionable. So far, I have replaced all the big
> > > caps
> > > on
> > > > > the pre-regulator and regulator boards. My feeling is that once
> these
> > > go
> > > > > online, they should run as long as possible between repairs.
> > > > >
> > > > > The battery charger circuit may need adjusting. I tweaked mine and
> it
> > > > > seemed to work fine.
> > > > >
> > > > > Todd
> > > > >
> > > > >
> > > > > On Fri, Aug 22, 2014 at 10:42 PM, Randy Evans <
> > > randyevans2688 at gmail.com>
> > > > > wrote:
> > > > >
> > > > > > I received my Fluke 732A today.  Just powered it up but it needs
> new
> > > > > > batteries.  Any suggestions for sources (I haven't opened up the
> unit
> > > > > yet -
> > > > > > I want to make sure it works before doing that).  Also received
> the
> > > > > > ProLogix USB-GPIB adapter.  I plan on using Mark Sims' CAL ran
> data
> > > > > dumper
> > > > > > program to get the CAL data from my 3458A.  Should be a busy
> weekend.
> > > > > >
> > > > > > Randy
> > > > > > _______________________________________________
> > > > > > volt-nuts mailing list -- volt-nuts at febo.com
> > > > > > To unsubscribe, go to
> > > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> > > > > > and follow the instructions there.
> > > > > >
> > > > > _______________________________________________
> > > > > volt-nuts mailing list -- volt-nuts at febo.com
> > > > > To unsubscribe, go to
> > > > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> > > > > and follow the instructions there.
> > > > >
> > > > _______________________________________________
> > > > volt-nuts mailing list -- volt-nuts at febo.com
> > > > To unsubscribe, go to
> > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> > > > and follow the instructions there.
> > >
> > > _______________________________________________
> > > volt-nuts mailing list -- volt-nuts at febo.com
> > > To unsubscribe, go to
> > > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> > > and follow the instructions there.
> > >
> > _______________________________________________
> > volt-nuts mailing list -- volt-nuts at febo.com
> > To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> > and follow the instructions there.
>
> _______________________________________________
> volt-nuts mailing list -- volt-nuts at febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
> and follow the instructions there.
>


More information about the volt-nuts mailing list