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This topic has been opened above but let’s break it down. Let’s say we have a float switch in a tank. The float dangles six feet down into a well. Let’s say that at 5 feet down into the well, the cord of the float switch is anchored to a metal bracket. From what we discussed above, this means that the float switch has “1 foot of tether”. Great. As the water goes up and down, at extremes, the float can be 1 foot above – or 1 foot below the anchor point. But don’t think for a minute that anything happens when the float is all the way up, or all the way down. All the action happens at 2 points in between. When water first touches the float – what happens? Nothing. The float is in its resting state. Water touches the float – maybe the ”float switch” is even floating on the water. Still nothing. You’re thinking “what are you talking about? Its called a float switch!”. We get it. That float needs to lift past the anchor point (a full foot!) and after it is above it, the float will change state (i.e. NO becomes NC, and NC becomes NO).
The question becomes “how far does it go”. That’s where “wide angle” and “narrow angle” come into play. Wide Angle float switches are generally “45⁰” floats. This means that when the float switch from our example is about 6” above the anchor point, the ball or the mercury will inside of it will move enough to change the state. And when the level comes back down, at about 6” below the anchor point, the state will change again. When the float is exactly at the elevation of the anchor – its at 0⁰ (zero degrees). The “45⁰” term means that (if we consider the anchor point to be the center of clock), that it changes state at 1:30 and 4:30. So from our example, our “1 foot of tether” produced 1 foot of difference between the switching points.
Narrow-angle float switches can be between 15⁰ and 25⁰. So, from the same switch we would cut that 1 foot down to 6” or less. Why would anyone want a “narrow angle float switch”? Well, if you want to fill a tank to the very top, or make sure that you know precisely a certain level, that may call for a “narrow angle” switch.
This is another place where Sump Alarm sees the world differently. Here’s what nobody tells you: For ball activated float switches – the ball can roll at a slightly different level depending on how the switch is installed. If you want a “narrower angle” – shorten the tether. We don’t make 10⁰, 15⁰, 20⁰, 30⁰, and 45⁰ floats. We make nearly all 45⁰ float switches. If it’s 45⁰, the math is easy. 6” of tether means there is 6” between state changes.