[TowerTalk] FW: UST Tower MA770 Starting Motor Capacitor

[Leeson]

A safety point: A good motor cap can hold the instantaneous value of the 
alternating voltage at the moment of disconnect. It's good to short it 
before touching the terminals. I use a jumper, and the zap and arc at 
times is quite surprising.

Dave, W6NL/HC8L

On 1/31/24 1:31 AM, maflukey at gmail.com wrote:
> Starting caps come in value ranges. My experience is that slightly higher
> values generally pose no issue, whereas too small may not be enough to get
> the motor started under load.    Try it to confirm.   If motor stalls on
> startup, stop and go to a larger cap.
> 
> Hope this helps and good luck on your project.
> 
> 73
> Matt
> KM5VI
> 
> 
> 
> -----Original Message-----
> From: TowerTalk <towertalk-bounces at contesting.com> On Behalf Of Joe Subich,
> W4TV
> Sent: Tuesday, January 30, 2024 7:52 PM
> To: Raymond Benny <rayn6vr at gmail.com>; [TowerTalk]
> <towertalk at contesting.com>
> Subject: Re: [TowerTalk] UST Tower MA770 Starting Motor Capacitor
> 
> 
> 
>   > How rigid is the 375MFD value?
> 
> Not that rigid ...
> 
>> I have found on eBay a cap, 378-454 uF MFD at 250VAC. Would this meet
>> the starting cap value?
> Easily.
> 
> 73,
> 
>      ... Joe, W4TV
> 
> On 1/30/2024 8:39 PM, Raymond Benny wrote:
>>    I've had a MA770 tubular tower in the air for the last 15 years. I
>> got it second hand 20 years ago. It's probably 40 years old. I need to
>> replace the raising motor starting cap.I have the old cap in my hand
>> and all I can read is 375 MFD. The motor operates on 120VAC. The motor
>> name/data plate has been painted over, so I cannot read anything about
>> it
>>
>> I have several questions:
>> Does anyone have the make, model number or manufacturer info for MA770
>> motor? And the info on the starting cap?
>>
>> How rigid is the 375MFD value? I have found on eBay a cap, 378-454 uF
>> MFD at 250VAC. Would this meet the starting cap value? I know I don't
>> need 240 VAC rated, but one rating should not be a problem. The
>> measurements given for the cap will fit into the external cap holder.
>>
>> Thanks,
>> Ray,
>> N6VR/W7YA
>>
> 
> 
> 
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