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AC Current Detector
Compares the AC input to a fixed or adjustable current limit. The output is an isolated switch or relay that is activated as required. Products available in clamp-on and pass-thru configuration.
AC Current Transducer
Maintain isolation and provide an analog DC output directly proportional to AC input current. True-RMS and average responding products are available in clamp-on and pass-thru configurations.
AC Power Transducer
Provides an isolated analog DC output directly proportional to AC input power. True power (watts) and volt-amp-reactive (VAR) transducers are available for a variety of power ranges and frequencies.
AC Voltage Transducer
Produce an isolated analog output signal directly proportional to AC voltage at a variety of frequencies. High sensitivity versions are available with zero suppressed AC input voltage ranges.
Accuracy
The deviation of the output signal in percent of full scale from a direct proportionality to the measured input at 25 degree C. Example: Accuracy +/- 0.5% F.S. means that a 0 to 5 VDC signal can vary to within +/- 25 millivolt at 25 degree C.
Average Responding
The transducer's DC output signal is calibrated to be proportional to the true RMS value of an ideal sine wave, i.e., 0.707 of the sine wave peak.
Bandwidth
The input frequency range over which the transducer will accurately respond.
Bi-directional
Provide an isolated bi-polar output directly proportional to the input current. The output signal tracts the input current waveform and recreates almost any AC, DC, transient or complex current combinations.
Common Mode Rejection
The AC signal to noise rejection ratio of the transducer when the input is connected in the differential configuration. Usually measured in decibels (dB).
Crest Factor
The ratio of the peak value of a wave form to its RMS value. As a specification, this indicates the degree of input distortion under which the transducer can continue to provide an accurate output.
DC Current Detectors
Compares the DC input to a fixed or adjustable current limit. The output is an isolated switch or relay that is activated as required. Products available in clamp-on and pass-thru configuration.
DC Current Transducers
Monitor DC current by providing a magnetically isolated analog output that is directly proportional to the input. Low current ranges are available for differential and ground fault current monitoring.
DC Voltage Detector
Produces an isolated analog output proportional to DC voltage.
DC Voltage Transducer
Compares the DC input to an adjustable threshold. The output is an isolated relay that activates as required.
Dielectric
Refers to the dielectric strength or the minimum voltage at which breakdown occurs between the transducer terminals and the transducer case (see Isolation).
DO-160
Refers to a composite environmental and physical specification normally required for equipment to satisfy flight worthy capabilities.
Frequency Transducers
Provides an isolated analog DC output signal directly proportional to AC input frequency.
Input AC Burden
The maximum amount of power consumed by the transducer from the input measured variable when at full scale value.
Input Frequency
Frequency range over which the measured variable can be applied without degradation of transducer performance.
Input Overload
The amount by which the input variable can exceed its full scale range without causing possible catastrophic damage to the transducer. This data is provided for continuous or transient overloads or both.
Isolation
A statement of the electrical isolation between the terminals, the case and input variable. Isolation is usually quantified in kilovolts or meg-ohms.
Load Resistance
The maximum resistive impedance that can be applied to a transducer's 4-20mA output loop at predetermined power supply voltage. The maximum load resistance varies as a function of the power supply voltage.
Loop Power
A standardized method of supplying power to a transducer from a remote process control system. In this case, the transducer output becomes an element in the process loop allowing 4 to 20 mA to flow according to the value of measured variable.
Loop Protection
Indicates that the transducer will not fail or be damaged in the event the loop power is reverse polarity connected.
Mil Grade
Refers to the following composite environmental and physical specifications, some of which are further defined in applicable MIL-Standards and DoD Stds. Series so noted meet or exceed these specifications:
- Altitude - sea level to 60,000 feet
- Attitude - unit will perform as specified when mounted in any position
- Dielectric Strength - 350 volts RMS (all terminals to case)
- Insulation Resistance - 100 Meg-Ohms (all terminals to case)
- Moisture Resistance - method 106 of MIL-STD-202 and method 507.1 Proc. Of MIL-STD-202
- Operating Humidity - 0 to 95% Relative Humidity
- Shock - operating 50 G, 11 milli-sec half sine pulse method 213, condition A of MIL-STD-202
- Vibration - operating 0.06 inch double amplitude, 10 to 55 Hz, method 201 of MIL-STD-202
Non-intrusive
Indicates that the transducer does not contact or electrically connect to the current carrying cable. The current carrying system will continue to operate independent of the operational status of the transducer.
Output @ Overload
Indicates the output signal that will result from the input measured variable exceeding the full scale rating. For most units, the output will remain linear to 120% of full scale and then saturate without transducer malfunction.
Output Impedance
The impedance presented by the output terminals to a load.
Output Protection
Level of misapplied or short circuit condition at the transducer's output signal terminals that will not cause failure of the transducer.
Output Signal
Output of the unit responding to the minimum value of input variable to full scale value.
Phase Angle Error
The degree of accuracy of the measured phase angle between current and voltage in a power transducer ( See Power Factor).
Power Factor
The ratio of the total active power to the apparent power. For sinusoidal wave forms, power factor corresponds to the cosine of the phase angle between the current and the voltage.
Power Supply
A specification that indicates the nominal supply voltage, the allowable variation in supply voltage and the nominal or maximum power consumed.
Range
The minimum to full scale input over which the transducer is calibrated.
Range Adjustment
In reference to frequency transducers, the output signal can be adjusted to full scale (5 volt DC) value from 100% to 50% of the measured input full scale frequency value. Range adjustment also refers to the variability of setting of the full scale output value.
Reflected Ripple
The level of AC noise that the transducer may reflect onto the input line. Usually expressed in millivolts RMS.
Repeatability
A measure of agreement of repeated measurements of the same input variable under the same conditions. Repeatability is usually expressed as a percentage of full scale of the output.
Response
The total time required for the output to respond to a defined level of steady state condition as a result of a sudden change in input variable. In DC and Bi-directional units response is the sum of both delay time and rise time and is typically measured in micro-seconds. In an AC unit this includes the number of cycles to reach acceptable averages and is typically in milli-seconds or cycle count.
Ripple
A measure AC noise on the DC output signal, usually expressed in RMS terms.
RMS Responding
The unit responds to the root-mean-square value of the measured variable over a full cycle. In the case of a pure sinusoid, this is 0.707 of the peak value.
Scale Factor
The ratio of the change in output to the change in input of the measured variable. Scale factor is a measure of the gain of the transducer.
Sensitivity
The highest input signal level (maximum) that can be applied without causing an output response and lowest input signal level (minimum) that is guaranteed to cause an output response.
Set Point
Either factory or user adjustable point at which the measured input variable will cause the output signal to move (trip) to a new state. This usually takes the form of a relay activation.
Stability
The ability of the transducer to maintain a steady state output signal with the same input measured variable over a very long time period. Stability is usually defined as a percentage of full scale output over one year period.
Supply Burden
See Power Supply.
Supply Protection
Levels of over voltage or reverse current at the supply terminals that the transducer can withstand without possible catastrophic failure. In addition, the transducer will also usually protect the power source from excess reverse current drain.
Suppression Voltage
Input measured voltage below which the output signal will remain at zero (0). Accuracy of this value is usually expressed as a percentage of the nominal "V minimum".
Temp Coefficient
Expressed as a percentage of full scale per degree C. Temp coefficient is the maximum change in output signal resulting from a change in operating temperature.
Temperature
Two ranges are normally specified, the range over which the transducer will operate properly and the range that the transducer can be subjected to without possible malfunction.
Time Delay Option
An available option on some transducers what will allow the user to adjust the delay time of the output signal response in excess of the normal response.
Transient Protection
Is the allowable input dv/dt and/or di/dt that the transducer can withstand without possible malfunction.
Trip Reset
The point at which the measured input variable in returning to its quiescent state causes the output signal to move (reset) to its former state. This usually takes the form of a relay deactivation.
Zero Adjustment
The ability to set the output signal minimum, for 0 input measured variable, at a range of values, usually given as a +/- percentage of full scale.
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