PRL-900
Wireless Pulse Link

Click photo for larger view

GENERAL DESCRIPTION

The PRL-900 Pulse Radio Link solves your short-hop pulse connection problems. In those hard-to-get-to applications, like "across the parking lot" where trenching is not economical, practical or possible, the PRL-900 Wireless Pulse Link allows you to connect an energy management system or other telemetry device to the electric meter's KYZ pulse output without the hassle. No more worrying how to run wires between the two devices.

The PRL-900 Pulse Radio Link consists of the PRT-900 Transmitter and PRR-900 Receiver. Each end also contains a base unit where all terminations are made. The system operates in the 900 MHz band and allows unlicensed operation by the end- user. The PRL-900 will transmit pulses up to 1000 feet in a line-of-sight configuration. Longer distances are possible with greater elevation above the ground and in areas where no metal objects or trees can cause interference, reflections or loss of the RF signal.

PRT-900 TRANSMITTER

The PRT-900 Transmitter consists of the Transmitter/Antenna unit and a Transmitter Base unit. The Transmitter/Antenna unit contains the radio transmitter and is designed for outdoor mounting. The Transmitter Base unit contains the power supply and provides terminating points where all connections are made. It is intended to be mounted either inside or in a raintight enclosure (optionally available). Transmitter/Antenna unit is connected together by an 8-conductor #24AWG control cable, up to 100' from the Transmitter Base unit and must be mounted in an unobstructed line-of-sight with the Receiver/Antenna unit.

The PRT-900 contains two Form A or Form C channels. Each time a pulse is received from the meter's KYZ pulse output, the transmitter validates this pulse and sends it to the receiver. Redundant communications of pulse status are used to ensure the accurate number of pulses is sent. The PRT-900 consumes extremely low power and can be operated in the normal mode or the super low-power mode for use with batteries or solar cells, or in applications where pulse speed is not greater than one pulse per second. The normal-mode pulse rates can be as high as 8pps for Form C and 4pps for Form A contacts. Up to two PRT-900's may be configured to be used with one PRR-900 receiver, such that pulses from two different meters may be brought to one receiver's location. The PRT-900 has a built-in low voltage transformer-isolated power supply generating a +13VDC sense (wetting) voltage. The sense voltage is connected to pulse sending devices, usually the "K" terminal of an electric meter's KYZ pulse initiator. The PRL-900 may be used with meters having mechanical output contacts (relays), or high or low voltage semiconductor outputs.

PRR-900 RECEIVER

The PRR-900 Receiver consists of a Receiver/Antenna unit and a Receiver Base unit. Each time pulse data packet transmission is received from the transmitter, the receiver validates the pulse and switches the respective output to the correct pulse state. The PRR-900 contains a software algorithm which detects missions pulses and corrects the pulse count should a pulse transmission ever be interrupted. The outputs' pulse widths are virtually identical to the transmitter's inputs, providing not only the correct energy consumption information but correct demand information as well. The PRR-900 contains two solid state KYZ Form C outputs with built-in MOV transient protection eliminating the need for external or off-the-board transient suppressors. Each output operates independently according to the state of the input of its respective transmitter channel. The Receiver/Antenna unit contains the radio receiver and is designed for outdoor mounting. The Receiver Base units contains the power supply, output relays and provides terminating points where all connections are made. It is intended to be mounted either inside or in a raintight enclosure (optionally available). The Receiver/Antenna unit is connected together by an 8-conductor #24AWG control cable, up to 100' from the Receiver Base unit and must be mounted in an unobstructed line-of-sight with the Transmitter/Antenna unit.

Typical applications include interfaces between utility metering devices and customer-owned energy control systems, telemetry, demand recorder applications, and supervisory control systems (SCADA) interfaces.

Bright red and green LED lamps on both the Transmitter Base unit and the Receiver Base unit indicate the inputs' and outputs' status at all times thus allowing a rapid check of the system's performance without requiring any additional test equipment. The PRR-900 Receiver Base unit contains a 3-LED bar graph which acts as a signal strength meter to give a visual indication of signal strength received from the transmitter. In longer distance applications, marginal or poor signal strength can be easily detected using the integral bar graph without the need for any special radio instrumentation or measurement equipment.

The PRL-900's input and output circuit's terminal strip on each base unit is a "EURO" type connector strip. When the stripped wire has been correctly installed in the terminals "slot" no conductive parts are exposed on the surface of the terminal strip, thus allowing the user maximum protection from accidental electrical shock. Each "K" lead of the PRL-900's outputs is fused to prevent damage to the relays under almost any conditions a user might cause such as excessive current, incorrect wiring, etc. A spring loaded connector for connection to each radio unit is provide which allows positive connections of the #24 AWG wire with no special tools required.

The PRT-900 and PRR-900 Radio units are mounted in a PVC weather-proof and sunlight resistant enclosure. Two plastic mounting brackets are provided for each radio for mounting on non-metalic surfaces. The radio units must be mounted at least 6.25" away from any metalic pole or building surface. Optional heavy-duty aluminum mounting brackets are available.

Each Radio's Base includes a mounting base plate and cover made of polycarbonate and offers excellent electrical insulation between the circuit and the mounting surface.

FCC Certified.

PRL-900 SPECIFICATIONS

ELECTRICAL

Power Input 120VAC, 208-277VAC; Burden: <10 MA. at 120 VAC
Signal Input to Meter: +13VDC wetting voltage generated by the PRT-2 Transmitter Base unit.
Output Two sets of "dry" form "C" contacts (K, Y, & Z) for energy pulses. The contacts are solid state "no bounce" relays rated at 350 VDC or 250 VAC 1/10th Amp. Factory fused at 1/10 amp. (3AG)
Output Contact Resistance 18 ohms typical, 25 ohms maximum
Input/Output Isolation Voltage: 3750 V
Operate and Release Time 1 to 3 milliseconds typical for solid state relay; Total propagation time up to 100mS.

MECHANICAL

Mounting Any position
Size 3.27 inches wide, 5.65 inches high, 1.50 inches deep
Weight 2 pounds each

TEMPERATURE

Temperature Range -38° C to +70° C, -36.4° F to +158° F
Humidity 0 to 98% non-condensing

OPTIONS

Input Voltages 125 VDC input using the DCS-1 Power Supply. Contact factory for other input voltages.