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Gunner Asch[_6_] Gunner Asch[_6_] is offline
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Default Back in service was : Compressors - kinda on topic !

On Wed, 5 Dec 2018 21:06:28 +0000, David Billington
wrote:

On 05/12/2018 20:30, Gunner Asch wrote:
On Wed, 5 Dec 2018 06:30:23 -0600, Terry Coombs
wrote:

On 12/4/2018 2:10 PM, Gunner Asch wrote:
On Tue, 4 Dec 2018 11:51:13 -0600, Terry Coombs
wrote:

* Well , I visited the neighbor , his compressor motor is also a 6 hp
Doerr motor so I borrowed his 189-230something start cap to test . My
motor spun up just fine with the belt off but wouldn't quite go with a
load . So I went to town and bought 2 , one at 243-292 and one at
340-408 . It will start under load with the smaller one ,
start under load? You dont have an unloader on your compressor???

__

"Poor widdle Wudy...mentally ill, lies constantly, doesnt know who he is, or even what gender "he" is.

No more pathetic creature has ever walked the earth. But...he is locked into a mental hospital for the safety of the public.

Which is a very good thing."

Asun rauhassa, valmistaudun sotaan.


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* Yes of course there's an unloader on it - in fact the tank was empty
this morning . But it was also 26° outside this morning , and there is a
load just from friction and cold oil . This compressor has always
started a little slow in cold weather , sometimes tripping the internal
overload . I usually leave it off unless I need it during the really
cold spells .

If its popping the overloads..you dont have them of the proper value.
If its a "contactor" type..increase the trip value (typically a tiny
blue plastic screw). If its a circuit breaker..increase the amps by 10
and retry.


It could also be the wrong class of breaker if that's what's tripping.
I've seen motors on lighting rated circuits tripping because the breaker
characteristics are not suited to motor start-up surges even when the
nominal motor current is well below the breaker current. Replacing the
breaker with a suitably rated breaker sorted the issue.


Excellent post!

I installed an elderly Cincinatti #2 centerless grinder in a shop a
couple weeks ago. They have (2) motors in them..the 4 hp "regulating
motor" and a 15-25hp Grinding motor. This machine was set up on a
220vt 30 amp breaker..which of couse is half of what the minimum
breaker should be. The moment the big motor came on line..it of
course popped the breakers. When I found the small breakers..I
installed 60 ampers..as most..most of these machines require a minimum
60s. I ampprobed the start up on this motor..and it was 273 AMPS -/+
!!! Run current was 32 amps and only went up and down a couple amps
under a load.

So I had to order a "slow blow" type breaker and I increased the amps
to 70 amps..I had no other choice besides installing a Slow Start box.
I may have to install a slow starter..simply because the rating of
that end of the building is only 200 amps..and it has to share power
with 4 other machines. Walter CNC grinders..so as it stands right
now..they have to power this machine up first..before anything
else...and once its warmed up and running..they can turn on the other
machines. They were not..not amused by this....(Grin)

The machine came from one of my least favorite A list dealers....

Ive seen him sell some really..Iffy machines and have had to fix them
after they were purchased..$adly.

Gunner
__

"Poor widdle Wudy...mentally ill, lies constantly, doesnt know who he is, or even what gender "he" is.

No more pathetic creature has ever walked the earth. But...he is locked into a mental hospital for the safety of the public.

Which is a very good thing."

Asun rauhassa, valmistaudun sotaan.