My goats, cows and horses seem to be getting shocked when drinking from the water trough and will only lick at the water.Tongue shocking while drinking is a very common occurrence. Livestock water troughs with tank heaters or troughs situated close to your electric fence are the most common scenarios. Both of these problems are fairly easy to fix.
It might be that you animals are being shocked with "stray voltage". Cows, horses and goats specifically, are very acute to electric shock or even if there is electricity flowing down a wire, before they ever touch it.
First of all, electric fencing is used to keep animals away from stuff. I would say in all instances that it would not be anyone's intention to keep your animals away from the water trough. The best solution for stray voltage from your electric fence is to move your water trough completely away from the electric fencing. If that is not possible, install a ground rod near the water trough in a place that is most often wet. You will need to attach a ground wire to the rod you pounded in the ground (soil) and attach the other end of the wire to the ground post on your electric fence energizer. this should take care of your "stray voltage" from the electrical fence.
Tank heaters almost never short out while under the water. If this were to happen, the breaker would most certainly trip and cut the power almost immediately. What does happen fairly often is that "stray voltage" is carried through the ground wire and into the trough, as the animal drinks, the circuit is completed and a slight shock occurs at the tongue. Purchase a 3-pronk to 2-prong adapter from any hardware store. Plug the tank heater into the adapter and the adapter into the electric source. Pound a ground rod into the soil close to the plug. Firmly attach a ground wire to the ground rod and the other end to the eyelet on the adapter. There you have it, you have stopped the "stray voltage" and provided a great ground for your tank heater.
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