Frquently Asked Questions

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What percentage of water and or coolant is acceptable for the CAP-300?

The CAP-300 is useable from 100% water to 100% coolant or any mixture of coolant and water.

What is the function of the CAP-300?

It is a point level sensor for applications such as power generation equipment, off highway vehicles and cell phone tower generators. The sensor’s protruding black electrode detects the presence or absence of the liquid medium which is composed of 0-100% mixture of Glycol based coolant and water, and actuates a solid state switched output.

What is the signal output logic for the CAP-300?

Open collector, Sinking NPN or Sourcing PNP output, 9-32 VDC, 30mA max.

What electrical terminations are commonly offered for the CAP-300?

3 pin Deutsch, 18 AWG type SXL flying leads or 18 AWG PVC cable.

Does the CAP-300 have circuit protection?

Reverse voltage: up to 45VDC; Overvoltage 80VDC min. Meets requirements of ISO 7637-2. Output protected against shorts to ground or supply.

If the composition of the coolant changes overtime, will the CAP-300 have to be recalibrated?

Recalibration will not be necessary if the coolant changes, the sensor will continue to operate.

Will the CAP-300 require maintenance?

Nearly zero maintenance, the sensor is small in size, tolerates coating and will remain reliable even in the standby mode.

Will density, opacity and viscosity variation as well as the accumulation of debris and chemicals found in the common coolants impair the sensor’s ability to detect the presence or absence of the medium?

It is not likely that this will affect the sensor.

Should I be concerned with moisture intrusion with the CAP-300?

It is a sealed design which prevents fluid intrusion.

What approvals does the CAP-300 have?

It currently has CE, IP67, RoHS, and IP6K9K.

What is the delay time for the CAP-300?

Standard units come with no delay. The response time is less than one second. For low quantities, we can offer a 5 and 10 second delay. Tolerance +/- ½ second. Gems can also customize the delay up to 99 seconds for large volume OEM applications. Call Gems for more information.

Delays are useful when the liquid being sensed is subjected to frequent sloshing or the reservoir’s attitude changes significantly.

What is the best orientation and mounting for the CAP-300?

The sensor is functional in any orientation. Mating customer surfaces shall be kept a minimum of 0.1” from any surface of the black plastic electrode. Gems recommends that the black sensing tip is not recessed into the side of a tank or adapter fitting because liquid (or air) may become trapped leading to false signals. Consult the factory for advice in this situation.

Will the CAP-300 work for an oil application?

The current design is specifically for conductive coolant applications. The dielectric of oil is too low and will not work with the current design.

What is the default dielectric constant for the CAP-300?

The sensor switching threshold is factory set at a Dielectric Constant (Dk) value of 30. Media with a Dk greater than 30 will be detected as “WET”. Conversely, media with a Dk less than 30 will be detected as “DRY”.

What Is the Mean Time Between Failure rate for Cap-300?
MTBF: 146,426.61 hours for ground mobile applications which are more severe.
What is Failure Rate for Cap-300?
Failure Rate: 6.820PPM Hrs.