Phase Angle Measurement

Phase angle in degrees indicates the phase lead or lag between two periodic signals of the same period, as determined from their zero crossings. These two signals will typically be the voltage and current applied to a load. As illustrated, the phase angle in degrees is +360*P1/P.

The Laureate phase angle transmitter transmits the lead or lag in degrees from 0° to 360° between two periodic signals of the same period. In the illustration to the right, phase angle is 360*P1/P. The signals are applied to the Channel A and B inputs of the Laureate dual-channel pulse input signal conditioner board. A resolution of 1°, 0.1° or 0.01° is selectable. Accuracy is 0.01% up to 100 Hz, 0.1% at 1 kHz, and 1% at 10 kHz.

### Power Factor Measurement

The power factor of an AC power system is the ratio of real power in watts (W) divided by apparent power in volt-amperes (VA). For sinusoidal signals, power factor is the cosine of phase angle.

The Laureate power factor transmitter computes power factor as the cosine of phase angle. Power factor readings can range from 1.000 to 0.000 with three decimal places and an accuracy of 0.1% for sinusoidal signals at 50/60 Hz power line frequency. While power factor is always positive, the meter artificially assigns a minus sign to power factor for negative phase angles, and it sets power factor to 0 for phase angles greater than 90°.

### Designed for flexibility

Phase angle and power factor are determined by timing crystal clock pulses over a specified gate time which is selectable from 10 ms to 199.99 s. By selecting the minimum gate time of 10 ms, the update rate can be up to 20/s for 50/60 Hz AC line frequency. Improved accuracy is obtained by making the gate time long enough so that multiple cycles can be averaged.

Exceptional Accuracy and Stability. Laureate transmitters determine frequency by taking the inverse of period as measured with a calibrated quartz crystal time base. This results in extremely accurate and stable 6-digit internal readings (±999,999 counts), which are then processed in software. The analog output is generated by an ultra-linear 16-bit (65,536 step) digital-to-analog converter (DAC) for 0.02% output accuracy. The update rate of the transmitter output is a programmed gate time + 30 ms + 0-2 signal periods. For a 60 Hz signal, the update rate would be 20 per second. Such fast update rates are ideal for alarm and control.

Standard features of Laureate LT transmitters include:

• 4-20 mA, 0-10V or -10V to +10V analog transmitter output, isolated, jumper-selectable and user scalable. All selections provide 16-bit (0.0015%) resolution of output span and 0.02% output accuracy of a reading from -99,999 to +99,999 counts that is also transmitted digitally. Output isolation from signal and power grounds eliminates potential ground loop problems.
• Serial communications output, RS232 or RS485 (half or full duplex), jumper selectable. Three protocols are user selectable: Modbus RTU, Modbus ASCII, or Laurel ASCII. Modbus operation is fully compliant with Modbus Over Serial Line Specification V1.0 (2002). The Laurel ASCII protocol is simpler than the Modbus protocol and is recommended when all devices are Laureates.
• Dual solid state relays, isolated, for alarm or control. Rated 120 mA at 140 Vac or 180 Vdc.
• Transducer excitation output, isolated. User selectable 5V@100 mA, 10V@120 mA or 24V@50 mA.
• Universal 85-264 Vac power. Low-voltage 10-48 Vdc or 12-32 Vac power is optional.

Easy Transmitter programming is via Laurel's Instrument Setup Software, which runs on a PC under MS Windows. This software can be downloaded from this website at no charge. The required transmitter-to-PC interface cable is available from Laurel (P/N CBL04).

### Features

• 4-20 mA, 0-20 mA, 0-10V or -10V to +10V transmitter output, 16 bits, isolated
• RS232 or RS485 serial data output, Modbus or Laurel ASCII protocol, isolated
• Dual 120 mA solid state relays for alarm or control, isolated
• Transmits phase angle between two AC wave shapes of similar period
• Transmits power factor from 1.000 to 0.000 with sinusoidal signals
• For frequencies from 0.005 Hz to 10 kHz, voltages from 10 mV to 250 Vac
• Phase angle resolution of 1°, 0.° or 0.01°, accuracy of 0.03% at AC line frequency
• Analog output resolution 0.0015% of span (16 bits), accuracy ±0.02% of span
• 5V, 10V or 24V dc transducer excitation output, isolated
• DIN rail mount housing only 22.5 mm wide, detachable screw-clamp connectors
• Universal AC power, 85-264 Vac, or low voltage power, 10-48 Vdc or 12-32 Vac

### Specifications

Phase Angle Mode
Item Transmitted Phase angle difference between two waves of same period
Transmitted Units 1°, 0.1°, 0.01°
Frequency Range .005 Hz to 10 kHz
Resution .01°, .005 Hz to 100 Hz, 0.1° at 1 kHz, 1° at 10 kHz
Accuracy 0.03° at 50 or 60 Hz
Maximum Timing Interval 200 sec
Power Factor Mode
Item Transmitted Power factor between two sine waves of same period
Transmitted Units 1.000 to 0.000, 1.00 to 0.00, or 1.0 to 1.0
Frequency Range 0.005 Hz to 10 kHz
Accuracy 0.1% at power line frequencies
Inputs
Signal Types Sinusoidal AC and square waves
Signal Ranges 10 mV to 250 Vac
Signal Ground Common ground for channels A & B
Noise Filter 1 MHz, 30 kHz, 250 Hz (selectable)
Update Rate
Conversion Interval Gate time + 30 ms + 0-2 signal periods
Gate Time Selectable 10 ms to 199.99 s
Time Before Zero Output Selectable 10 ms to 199.99 s
Analog Output (standard)
Output Levels 4-20 mA, 0-20 mA, 0-10 Vdc, -10 to +10Vdc (user selectable)
Compliance, 4-20 mA 10V (0-500 ohm load)
Compliance, 0-10V 2 mA ( kOhm load)
Output Resolution 16 bits (65,536 steps)
Output Accuracy 0.02% of output span plus conversion accuracy
Output Isolation 250V rms working, 2.3 kV rms per 1 minute test
Serial Data Output (standard)
Signal Types RS232 or RS485 (half or full duplex), jumper selectable
Data Rates 300, 600, 1200, 2400, 4800, 9600, 19200 baud
Output Isolation 250V rms working, 2.3 kV rms per 1 min test
Serial Protocols Modbus RTU, Modbus ASCII, Laurel ASCII
Modbus Compliance Modbus over Serial Line Specification V1.0 (2002)
Ethernet Connector RJ45 jack for 10/100 Base-T Ethernet cable
RS232/485 Connector Screw terminals for easy daisy chaining
Digital Addresses 247 for Modbus, 31 for Laurel ASCII
Dual Relay Output (standard)
Relay Type Two solid state relays, SPST, normally open, Form A
Load Rating 120 mA at 140 Vac or 180 Vdc
Sensor Excitation Output (Standard)
Output levels 5V@100 mA, 10V@120 mA, 24V@50 mA (jumper selectable)
Output Isolation 50V from signal ground
Power Input
Standard Power 85-264 Vac or 90-300 Vdc
Low Power Option 10-48 Vdc or 12-32 Vac
Power Frequency DC or 47-63 Hz
Power Isolation 250V rms working, 2.3 kV rms per 1 min test
Power Consumption 2W typical, 3W with max excitation output
Mechanical
Dimensions 129 x 104 x 22.5 mm case
Mounting 35 mm rail per DIN EN 50022
Electrical Connections Plug-in screw-clamp connectors
Environmental
Operating temperature 0°C to 55°C
Storage temperature. -40°C to 85°C
Relative humidity 95% at 40°C, non-condensing
Cooling Required Mount transmitters with ventilation holes at top and bottom. Leave 6 mm (1/4") between transmitters, or force air with a fan.

### Applications

Application Example
Using Laureate Meters, Counters or Transmitters to Synchronize Motor Generators

Synchronization of two motor generators requires that the two frequencies be identical, that the lines be in phase, and that the line voltages be close to each other. In this illustration, a single Laureate dual channel counter (or frequency transmitter) measures both frequencies to six-figure accuracy in a few line cycles. Another Laureate dual channel counter (or phase transmitter) measures phase angle to 0.1° resolution. Two Laureate AC RMS Voltmeters, which offer ranges of 200.00 V and 600.0 V, are used to display the two RMS voltage to 0.1% accuracy.
 Datasheet, Manual, Mechanical and Serial I/O info. Manufacturer site: https://www.laurels.com/transmitter-phase.php