Many thanks Tim for your comments. From what you've said it sounds like a faulty motor. In the ones you've repaired have you been able to determine the cause of motor over heating?
The problems I've had in the past have always been due to water getting into the units.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK
On 07/10/2011 18:50, Tim Cunningham wrote:
The common failure of the motor windings is caused by heat which causes the enamel coated wire to breakdown. When the enamel breaks down an inner winding short results.
I have successfully rewound motor windings on these rotators just to say it could be done, but it takes some work (not recommended).
I have never seen one of these motors with an open winding. The failure mode on the 8 that I have repaired were always enamel insulation breakdown as a result of overheating.
Tim - N8DEU
Sent from my HTC Tilt™ 2, a Windows® Mobile phone
-----Original Message----- From: Clive Wallisamsat-bb@g3cwv.co.uk Sent: Friday, October 07, 2011 11:35 AM To: amsatamsat-bb@amsat.org Subject: [amsat-bb] G5500 Elevation Rotator Short Circuit?
I wonder if this is a known fault. Recently the fuse on my G5500 blew. The problem seems to be a short on one of the motor circuits.
Checking the DC resistance at the control end, the resistance of one winding is 1.2 ohms, whereas all the other windings are 4.6 ohms.
I could understand a motor burning out and going open circuit, but a short circuit seems less likely. I'm wondering if it could be a short on the cable at the rotator end, where it is subject to much bending. There's about 15 metres of cable.
Any thoughts would be much appreciated. Unfortunately, at the present time I'm not able to inspect the rotator. It's stuck in the horizontal position, so I will still be able to use the antenna for low elevation passes.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
All of the failures were specifically attributed to either a stuck relay in the control box, a manual switch sticking (not releasing) on the front rotor control panel, and a software or computer crash that continued to drive one of the up, down, left, or right control lines.
73,
Tim - N8DEU
----- Original Message ----- From: "Clive Wallis" list1@g3cwv.co.uk To: "amsat" amsat-bb@amsat.org Sent: Sunday, October 09, 2011 11:50 AM Subject: [amsat-bb] Re: G5500 Elevation Rotator Short Circuit?
Many thanks Tim for your comments. From what you've said it sounds like a faulty motor. In the ones you've repaired have you been able to determine the cause of motor over heating?
The problems I've had in the past have always been due to water getting into the units.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK
On 07/10/2011 18:50, Tim Cunningham wrote:
The common failure of the motor windings is caused by heat which causes the enamel coated wire to breakdown. When the enamel breaks down an inner winding short results.
I have successfully rewound motor windings on these rotators just to say it could be done, but it takes some work (not recommended).
I have never seen one of these motors with an open winding. The failure mode on the 8 that I have repaired were always enamel insulation breakdown as a result of overheating.
Tim - N8DEU
Sent from my HTC Tilt™ 2, a Windows® Mobile phone
-----Original Message----- From: Clive Wallisamsat-bb@g3cwv.co.uk Sent: Friday, October 07, 2011 11:35 AM To: amsatamsat-bb@amsat.org Subject: [amsat-bb] G5500 Elevation Rotator Short Circuit?
I wonder if this is a known fault. Recently the fuse on my G5500 blew. The problem seems to be a short on one of the motor circuits.
Checking the DC resistance at the control end, the resistance of one winding is 1.2 ohms, whereas all the other windings are 4.6 ohms.
I could understand a motor burning out and going open circuit, but a short circuit seems less likely. I'm wondering if it could be a short on the cable at the rotator end, where it is subject to much bending. There's about 15 metres of cable.
Any thoughts would be much appreciated. Unfortunately, at the present time I'm not able to inspect the rotator. It's stuck in the horizontal position, so I will still be able to use the antenna for low elevation passes.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
The az on my 5500 quit working abruptly lst week. Disgnosis was fairly easy. I went out side and noted that the xyl had cut the az cable with the ztr. 73 George WA5KBH
-----Original Message----- From: "Tim Cunningham" tim_cunningham@charter.net Sent: Thursday, October 13, 2011 15:46 To: clive@g3cwv.co.uk, "amsat" amsat-bb@amsat.org Subject: [amsat-bb] Re: G5500 Elevation Rotator Short Circuit?
All of the failures were specifically attributed to either a stuck relay in the control box, a manual switch sticking (not releasing) on the front rotor control panel, and a software or computer crash that continued to drive one of the up, down, left, or right control lines.
73,
Tim - N8DEU
----- Original Message ----- From: "Clive Wallis" list1@g3cwv.co.uk To: "amsat" amsat-bb@amsat.org Sent: Sunday, October 09, 2011 11:50 AM Subject: [amsat-bb] Re: G5500 Elevation Rotator Short Circuit?
Many thanks Tim for your comments. From what you've said it sounds like a faulty motor. In the ones you've repaired have you been able to determine the cause of motor over heating?
The problems I've had in the past have always been due to water getting into the units.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK
On 07/10/2011 18:50, Tim Cunningham wrote:
The common failure of the motor windings is caused by heat which causes the enamel coated wire to breakdown. When the enamel breaks down an inner winding short results.
I have successfully rewound motor windings on these rotators just to say it could be done, but it takes some work (not recommended).
I have never seen one of these motors with an open winding. The failure mode on the 8 that I have repaired were always enamel insulation breakdown as a result of overheating.
Tim - N8DEU
Sent from my HTC Tilt™ 2, a Windows® Mobile phone
-----Original Message----- From: Clive Wallisamsat-bb@g3cwv.co.uk Sent: Friday, October 07, 2011 11:35 AM To: amsatamsat-bb@amsat.org Subject: [amsat-bb] G5500 Elevation Rotator Short Circuit?
I wonder if this is a known fault. Recently the fuse on my G5500 blew. The problem seems to be a short on one of the motor circuits.
Checking the DC resistance at the control end, the resistance of one winding is 1.2 ohms, whereas all the other windings are 4.6 ohms.
I could understand a motor burning out and going open circuit, but a short circuit seems less likely. I'm wondering if it could be a short on the cable at the rotator end, where it is subject to much bending. There's about 15 metres of cable.
Any thoughts would be much appreciated. Unfortunately, at the present time I'm not able to inspect the rotator. It's stuck in the horizontal position, so I will still be able to use the antenna for low elevation passes.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Thanks Tim.
I'm not aware of any problems with my controller or computer. I notice that there are micro switches to protect against over-run, and wonder why these didn't protect the motor, if one of the circuits had stuck on.
BTW have there been any improvements with the sealing against rain water on this model? It seems better than the previous model, in this respect.
73 Clive G3CWV
On 13/10/2011 21:46, Tim Cunningham wrote:
All of the failures were specifically attributed to either a stuck relay in the control box, a manual switch sticking (not releasing) on the front rotor control panel, and a software or computer crash that continued to drive one of the up, down, left, or right control lines.
73,
Tim - N8DEU
----- Original Message ----- From: "Clive Wallis" To: "amsat" amsat-bb@amsat.org Sent: Sunday, October 09, 2011 11:50 AM Subject: [amsat-bb] Re: G5500 Elevation Rotator Short Circuit?
Many thanks Tim for your comments. From what you've said it sounds like a faulty motor. In the ones you've repaired have you been able to determine the cause of motor over heating?
The problems I've had in the past have always been due to water getting into the units.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK
Most of the motors I repaired did not have the limit switches because they were early models. There was one the limit switch was broken and another that had limit switches that I could only attribute to excessive use that overheated and the windings to the point that the enamel broke down (of course, with no certainty). Lightning strikes were much easier to see.
Some of the early Kenpro units did not employ the protective limit switches.
The Kenpro KR-5400 did not have limit switches in either the azimuth or elevation rotors. The Kenpro KR-5600 employed limit switches only on the Azimuth rotor. The Yaesu G-5400 employed limit switches only on the Elevation and employed a thermal switch on the Azimuth rotor. The Yaesu G-5600 employed limit switches on both the Elevation and Azimuth rotor.
The Kenpro KR-5400 and 5400 employed the motor capacitors in the control box. The Yaesu G-5400 moved only the Elevation motor capacitor to the rotor, but left the Azimuth motor capacitor in the control box. The Yaesu G-5600 moved both motor capacitors from the control box to the Elevation and Azimuth rotors.
During Field Day when I had to swap from a Yaesu to Kenpro controller I had to utilize jumpers to add the 100uF capacitor to make the Kenpro Azimuth motor work. Everybody looked at this black plastic capacitor I jumpered on the back of the control box and I just told them it was my Flux Capacitor until some Engineer requested an explanation for its purpose.
73's, Tim - N8DEU
----- Original Message ----- From: "Clive Wallis" list1@g3cwv.co.uk To: "Tim Cunningham" n8deu@att.net; "amsat" amsat-bb@amsat.org Sent: Sunday, October 16, 2011 5:52 AM Subject: Re: G5500 Elevation Rotator Short Circuit?
Thanks Tim.
I'm not aware of any problems with my controller or computer. I notice that there are micro switches to protect against over-run, and wonder why these didn't protect the motor, if one of the circuits had stuck on.
BTW have there been any improvements with the sealing against rain water on this model? It seems better than the previous model, in this respect.
73 Clive G3CWV
On 13/10/2011 21:46, Tim Cunningham wrote:
All of the failures were specifically attributed to either a stuck relay in the control box, a manual switch sticking (not releasing) on the front rotor control panel, and a software or computer crash that continued to drive one of the up, down, left, or right control lines.
73,
Tim - N8DEU
----- Original Message ----- From: "Clive Wallis" To: "amsat" amsat-bb@amsat.org Sent: Sunday, October 09, 2011 11:50 AM Subject: [amsat-bb] Re: G5500 Elevation Rotator Short Circuit?
Many thanks Tim for your comments. From what you've said it sounds like a faulty motor. In the ones you've repaired have you been able to determine the cause of motor over heating?
The problems I've had in the past have always been due to water getting into the units.
73 Clive G3CWV
Hitchin, North Hertfordshire, UK
participants (4)
-
Clive Wallis -
gkcarr＠go-express.net -
n8deu -
Tim Cunningham