Hi all , I have not posted for a long time due to finding it almost impossible to use the site due to advertising. But it seems a little better now
Sorry this is a long one !
I have a client that is having severe trouble on a dairy farm with his cow's appearing the sense stray voltage as they step onto the rotary milking carousel and possibly whilst on it.
He is well over 300 miles away from our base and I've only been to site a couple of times for other issues.
He has had several other companies look into it and I am informed that all bonding is in place and there appears to be no significant faults on the farm.
He does have a variable drive vac pump , but this has apparently been checked as ok with appropriate earthing and filters in place.
Originally it was thought he was tncs with an added twig as an earth stake , so it got changed to TT.
He has a 40,000 stainless steel ex milk tanker from what I understand buried underneath the rotary parlour used as a water tank for the borehole water supply which is fed from roughly half a mile away.
When going TT I got him to dig a 20 foot deep hole about 40 foot from his mains room in which he has dropped numerous gates and metal troughs welded together and then denso taped up along with several 3/8 stakes laid sideways all connected up with 50 m of stripped 16 mm topped off with a good 10 bags of Benoite along with a drip feed of borehole water for good measure , and then 10 - 15 foot of top soil .
This was to try and get a better reading than the tank which is around 2.3 , but we can only get around 7.1
Subsequently it turns out it was a TNS supply anyway with a reading of 0,13 with the transformer only 50 or 60 foot away the other side of the yard so he's reconnecting that this week.
He has had monitoring equipment on a couple of weeks ago whilst running on mains TT and he appears to be getting high fifth and high seventh harmonics at milking times but also occasionally when the variable drives are not working.
Just to add , this has been going on and off for the last 18 months plus and at first when he went to generator only it seemed to cure it overnight only to come back the same as when he went TT ?
He has spoken to many people over this including dairy experts in New Zealand every time he tries something it seems to improve it for a day or two and go back to being a problem.
Has anyone got any ideas or pointers that may help ?
Many thanks
Dave
Sorry this is a long one !
I have a client that is having severe trouble on a dairy farm with his cow's appearing the sense stray voltage as they step onto the rotary milking carousel and possibly whilst on it.
He is well over 300 miles away from our base and I've only been to site a couple of times for other issues.
He has had several other companies look into it and I am informed that all bonding is in place and there appears to be no significant faults on the farm.
He does have a variable drive vac pump , but this has apparently been checked as ok with appropriate earthing and filters in place.
Originally it was thought he was tncs with an added twig as an earth stake , so it got changed to TT.
He has a 40,000 stainless steel ex milk tanker from what I understand buried underneath the rotary parlour used as a water tank for the borehole water supply which is fed from roughly half a mile away.
When going TT I got him to dig a 20 foot deep hole about 40 foot from his mains room in which he has dropped numerous gates and metal troughs welded together and then denso taped up along with several 3/8 stakes laid sideways all connected up with 50 m of stripped 16 mm topped off with a good 10 bags of Benoite along with a drip feed of borehole water for good measure , and then 10 - 15 foot of top soil .
This was to try and get a better reading than the tank which is around 2.3 , but we can only get around 7.1
Subsequently it turns out it was a TNS supply anyway with a reading of 0,13 with the transformer only 50 or 60 foot away the other side of the yard so he's reconnecting that this week.
He has had monitoring equipment on a couple of weeks ago whilst running on mains TT and he appears to be getting high fifth and high seventh harmonics at milking times but also occasionally when the variable drives are not working.
Just to add , this has been going on and off for the last 18 months plus and at first when he went to generator only it seemed to cure it overnight only to come back the same as when he went TT ?
He has spoken to many people over this including dairy experts in New Zealand every time he tries something it seems to improve it for a day or two and go back to being a problem.
Has anyone got any ideas or pointers that may help ?
Many thanks
Dave
