Highly efficient winches often times have a common feature which is having a low amp draw which means they do not use or drain too much power from your battery. Aside from this, there are many other features which manufacturers would claim other great and impressive features. Though that is the case, you cannot take these listed features at face value.
Yes, often times that the specs listed on the product description would usually describe their performance at optimum situation. Unfortunately, it is rarely that you would be at an optimum scenario in the real world. Hence, you would only know how your winch performs in a lab which is also the same with how much amp your winch draws. In fact, this is different in real world as your winch will definitely draw more amps that it is described and listed.
What Affects Amp Draw
As mentioned earlier, Amp would usually draw the amount of current which your winch would use. This would depend on how much your winch would pull. Hence, your amp draw would be affected by the factors that would make your winch work and strain harder.
Layers of Wrap
When winches are tested and rated especially for their strength and efficiency, manufacturers would usually test their winch having only one layer of cable wrapped around their winch drum. Unfortunately, in real life, you would be using more layers and the more layers you wrap around the winch drum the weaker the strength and efficiency become. Approximately, your winch would become 10% more inefficient. Hence, it is then, highly recommended to anchor your cable as far as possible. This way, your winch’ drum will not have numerous wraps.
Line Pull
As with the line pull, your winch would have to draw much more amp when your winch would have to deal with more load. The data below is just an example of this. Keep in mind, however, that the data provided below is a result of a single wrap of cable on your winch’s drum.
| Line Pull | Amp Draw |
| 0 | 71 |
| 2000 | 169 |
| 4000 | 248 |
| 8000 | 413 |
| 9500 | 482 |
Converting Horsepower to Amperes
Horsepower is the power which your motor or engine produces. It is the measurement which means that the electric power that your engine produced is equal to 746 watts. Knowing this is important as when you know the horsepower of your winch, then, theoretically, you would have an accurate estimate of the amp draw of your winch.
To understand this better, here is the simplest formula which is being used to convert HP to amps.
Amps =(HPx746W) Winch Efficiency V
HP = horsepower
W= watts
V= volts
Winch Efficiency = how efficient your winch is
