Wide Input Voltage Range
The ability of a device to operate within a wide supply band rather than being tied to a single nominal voltage. This way the same product can be used in vehicles with both 12V and 24V electrical systems without a converter. The AXI HCT402 works directly on both 12V and 24V systems; its voltage stability has been tested at the 7, 12, 27 and 31 V points and the product has reverse polarity protection.
A wide range is achieved by the switching regulator at the device input producing a stable internal voltage across a wide band. In practice it solves two different problems at once:
- Fleet variety: a 12V tractor and a 24V construction machine use the same product; there is no need to hold two separate models in stock.
- Voltage fluctuation: during cranking the supply collapses temporarily, and while running the alternator rises to the order of 13.8–14.4 V. The lower and upper ends of the range cover these two extremes.
For the HCT402 the manufacturer declares that the voltage stability has been tested at the 7, 12, 27 and 31 V points. These test points have been chosen so as to cover both the collapse during cranking on a 12V tractor and the charging voltage on a 24V construction machine. Because a single lower and upper limit figure is not given consistently in the product data, we do not write a numerical range here; the product's declaration is in the form of direct operation on 12V and 24V systems.
This does not mean unlimited protection: high-energy transient events such as load dump, and the voltages that arise during welding, are a separate matter. Before welding, the supply connection is disconnected.
Context in which this term is used: Converting a tractor hydraulic lever to electronic control