Chuck McManis wrote:
> 
> Are they 3 phase blowers or 2 phase blowers?

they are DC, 24 V DC 1.8 A. Most everything in the VAX 6000 is DC.

> Generally you can use an ohm
> meter to verify that the coils are not open, if they are then the only
> choice is to take them apart and re-wind them.

Good idea ... hmm weird. None of the coils are open. But
I can't get a sure reading off of any of them. It depends
on the level that's set for the maximum:

            broken working
20 kOhm   -  3.5    6.8
200 kOhm  - 19.0   19.0
2 MOhm    -  0.99   0.99

it seems like we get different readings for different 
resistors used for testing ... Computing the result that
I should get when in operation is 24 V / 1.8 A = 13.3 Ohm.
During rest this can be lower, but probably never lower 
than 13.3 because 1.8 A is probably maximum current.

The difference between the working one has 2 x as much 
resistance than the broken ones. May be this is an 
indication? But that's not consistent either because one
is working and has 3.5 too. 

> Any good electric motor shop
> can do this (they could also make them two phase for you :-) Look up
> appliance repair for a place that repairs industrial fans and blowers. 

Last resource, foreign labor costs are to be avoided :-)

> Also they are probably replaceable...

Yes, for $200 a piece at your favorite DEC parts ripoff
store :-) Or do you think these are some sort of widely
used industry standard? That would be cool.

regards
-Gunther 

-- 
Gunther Schadow, M.D., Ph.D.                    gschadow@regenstrief.org
Medical Information Scientist      Regenstrief Institute for Health Care
Adjunct Assistant Professor        Indiana University School of Medicine
tel:1(317)630-7960                         http://aurora.regenstrief.org