VDO Style Temperature Sender
SeaGauge™ Sensor Interface Units support several types of resistive temperature senders in different case styles.
Senders vary resistance with changes in temperature usually with resistance decreasing as temperature rises. A pull up circuit supplies the bias voltage via a single wire with the ground return path via sender body to system ground. In some cases, a separate ground terminal can be ordered for isolated ground systems.
The main difference between senders is temperature range with operational ranges from 60F - 250F and 100F-350F the most common. These versatile senders are used for Engine Coolant, Water tank, Transmission OIL, Heat Exchangers, and more.
Resistive senders are effected by long wire runs which can increase the overall load. With max temperature resistance in the 20-40 Ohm range, the effect of lead resistance can become noticeable. These effects can be easily compensated via adjustments in calibration tables. Another effect of resistive senders is no-linear response curves which can cause very quick changes at end of operating ranges. Calibration tables can help reduce some of these effects.