[QuadList] Variacs and awakening gear from long naps (was Got my VR 1200's)

[Guy Spiller]

Hi Ted,
The TR-70 has three separate AC line in circuits with a 30 amp TwistLoc 
on each. It can be jumpered for either 110 or 220, but every one I've 
ever seen has been set for 110v.
I made up a short Variac test cable with a regular 110v male plug and a 
TwistLoc female, and powered up one circuit of the 70 at a time. 
Actually, only two of the circuits power the machine itself, and the 
third is just for the auxiliary AC outlets and the flourescent tube 
above the transport, so no need to fool with that one. 
I did unplug the headwheel blower and the combo vacuum pump/main cooling 
blower so they wouldn't heat up trying to start on low voltage.
It worked out great, since my Variac can only do 15 amps, and that's 
very close to what each of the three circuits in the 70 actually pulls.  
I just ran up each of the two machine circuits separately.
I stopped the process when I got to around 50 volts, as that's when 
various relays started audibly complaining.  I think most of the good 
from this process, at least on a 70, occurs below 50 volts input.  I 
monitored the voltage of each of the DC rails all the way from zero up 
to 50 volts input, and it was a very linear progression, so I had a good 
sense that all was working as planned and no caps were shorted anywhere. 
Guy

Ted Langdell wrote:
> How many amps can it handle?  (Obviously enough to deal with a 
> TR-70... ;)
>
> Does it have the usual socket for your TR-70 wall plug or did you have 
> to modify something?
>
> Ted
>
> _______________________________________________
>

Guy Spiller
email: quadruplex at verizon.net
phone: (804) 379-2050
website: www.GuySpiller.com
Midlothian, VA