[ARC5] Dynamotor Regulation

[WA5CAB at cs.com]

The PP-7773 may have internal protection (or you would have already blown 
the pass elements) but in general, you need a high current diode in series 
with the power supply output if you don't know that it already has such.  
There was a period years ago before we designed and built dedicated chargers 
when OPS tried to use HP current regulated bench supplies to re-charge our 
Silver-Zink battery packs.  We had to pay US Instrument Rentals for several 
supplies from failing to disconnect the battery before turning off the supply.  
And in the field, several instances caused by unreliable mains supply.

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480

In a message dated 07/29/2017 08:38:49 AM Central Daylight Time, 
aj1g at sbcglobal.net writes: 
> For the ARC-5 /274 systems you can easily get by with 2 20 buck garden 
> tractor batteries from Walmart in series each floated with a separate 10 amp 
> 12 battery charger.  I have been using that type of set up for over 30 
> years with two basic Sears chargers.  I also use the small garden tractor 
> batteries in series across my PP-7773 60A 28vdc supply to run my ART13/DY17A 
> setup.  However, the small batteries don't have quite enough oomph to prevent 
> the DY-17 starting surge from tripping the 7773 output breaker, l usually 
> have to reclose it once the dyno is running.  With fully charged bigger deep 
> cycle marine or car batteries the breaker usually will not trip.  I have 
> also found from experience with the 7773 that you need to physically 
> disconnect the batteries from across the output of the supply when it is shut 
> down.  There is some drain on the batteries from the 7773 even with its output 
> breaker open, from at least the voltmeter circuit,  which will drag down 
> the batteries over several days.  I just disconnect the lead between the two 
> batteries to put them on open circuit.
> 
> 
> 
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