RD500 Water Pipe Locator Kit

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Thank you for purchasing the most cost-effective plastic pipe locator tool available. The purpose of this manual is to provide useful information that will help you get the best possible results from your new locator. This operating guide contains directions for unpacking, setting up and operating the RD500 system. It also contains a fast start guide that will enable users to quickly begin locating water pipes. This is followed by more detailed instructions for obtaining better results with the Pulse Transmitter and the Locator



Unpacking and Set-up

Your RD500 Locator comes packaged in a special carrying case that has compartments for the Locator with spike installed, a hard surface plate and the headphones. Each kit that you order is pre-assembled and ready for use. Please keep all packaging materials in case it becomes nec­essary for you to return any of your equipment. The following items should be checked as you unpack your system.

LOCATOR: The Locator is supplied with a 9-volt battery and ground spike installed. A hard surface plate and headphones are also included along with this operation manual. If any items are missing please contact your Radiodetection supplier immediately.

PULSE TRANSMITTER KITS: Each Pulse Transmitter adapter kit comes fully assembled and ready for use. A detailed drawing of each Adapter Kit is contained in Section 5.0 of the Oper­ational Manual. . If any items are missing please contact your Radiodetection supplier immediately.

Fast Start Guide

Detailed operating instructions are also included on the side of the Locator. These instructions are repeated her for your convenience:

Pulse Transmitter Operating Instructions

  1. Remove protective caps from Pulse Transmitter
  2. Connect Pulse Transmitter to nearest water outlet using kit supplied with Pulse Transmitter
  3. Turn on water and loosen adjustment lock nut near T-handle
  4. Turn T-handle clockwise until water flows
  5. Turn T-handle anticlockwise until water pulses several times per second; tighten lock nut

Locator Operating Instructions

  1. Turn ON/ OFF knob clockwise to activate
  2. Initial meter reading indicates battery condition
  3. To replace battery, loosen battery release button, move housing upward to ex pose battery.
  4. Begin initial tracing about 2 meters from Pulse Transmitter or any other area where pipe location is known
  5. Push spike of Locator into ground near known pipe location and turn ON/ OFF knob clockwise for mid-range meter reading and adjust individual headphone controls for comfortable listening level
  6. To pinpoint pipe position, use Locator to probe ground until you find peak (maximum) meter reading. You will also hear the pulsing sound (similar to a heartbeat) grow louder
  7. Trace the pipe by establishing the direction of pipe route by probing every one to two meters to locate a peak meter reading. Adjust the ON/ OFF knob to maintain a mid-range meter reading

Notes and Precautions

  • The RD500 is for use on water pipes only
  • It works best on water pressures in the range of 3 to 7 Bars; maximum pressure 10 Bars
  • The Pulse Transmitter pulsating effect causes pipe movement. If used for extended periods or on substandard plumbing systems, leaks may result

Additional Notes and Precautions

  1. RD500 readings do not indicate depth and the RD500 does not detect buried electrical power lines, gas lines or other hazardous underground objects, so always dig carefully in the proximity of buried pipes or cables
  2. Use caution while wearing headphones and be alert to traffic or other hazards that are normally heard outdoors
  3. Always stand clear of all Pulse Transmitters, adapter kits and hoses while they are connected to water systems and operating
  4. On all hose bib applications, within 15 meters (50 feet) of a building, the proper low-power Pulse Transmitter (GREEN) or RD500-Tx electronic Pulse Transmitter and Tap damper MUST be used

Pulse Transmitter Application Techniques

Pulse Transmitters are connected at sprinkler heads, hose bibs, water meter bases, fire hydrants and clean-outs. Supplied Pulse Transmitters using the adapter kits are illustrated in Section 5.0 of the Operational Manual. Always flush any connection site until the water that flows is clear of all rust, silt, sealing compounds and foreign materials before connecting a Pulse Transmitter to the water line.

Refer to Section 5.0 for a detailed description of the Locator kit and the adapter kits that are available. All adapter kits are supplied with a Tap damper, tap, couplings and a 3 meter (10 foot) high-pressure drain hose that must be connected to the outlet of the Pulse Transmitter in order for the device to work properly. Always use a weight on the hose or tie the hose down to prevent the hose from whipping.

Check the water pressure before attempting to locate the water line and make sure that it is in the operating range of the Pulse Transmitter, which is 3 to 10 Bars (40 to 140 psi).

The Pulse Transmitters are color-coded to identify their intended usage: A color-coded ty-wrap is used along with a small square area that is painted on the side of the Pulse Transmitter to indicate the color. Green is the lowest power Pulse Transmitter and is intended for use on sprinkler and hose bib pipes that typically range in diameter between 1.3cm and 5cm (0.5 inches and 2 inches). Green Pulse Transmitters may be may be used on larger diameter pipes where reduced operating range is acceptable. Yellow Pulse Transmitters are intended for use on water mains that range in diameter between 5cm and 15cm (2 inches and 6 inches). They are typically connected at a water meter connection. Yellow Pulse Transmitters should never be used on smaller diameter pipes, but they may be used on larger diameter pipes. Red Pulse Transmitters are intended for use only on water mains that are 15cm (6 inches) in diameter or larger. The typical connection is via a fire hydrant.

Always start your adjustments by turning the T-handle clockwise until full water flow is at­tained at the Pulse Transmitter outlet. Then, slowly turn the T-handle anticlockwise until the Pulse Transmitter begins to pulse. Once the pulsing begins, turn the handle very slowly in each direction to fine tune the pulse to a regular beat of about two to five times per second. This adjustment range varies between less than one turn to several turns depending on the oper­ating conditions. If you turn the T-handle too far in the clockwise direction, water will flow continuously without pulsing, and if you turn the T-handle too far in the anticlockwise direc­tion, water flow will stop completely.

The best results are obtained with the slowest pulse possible. Range and signal strength are greatly improved with low pulse rates of a few pulses per second. Higher water pressures typi­cally cause faster pulse rates. Pulse rates above 10 pulses per second are difficult to use and cause reduced location range.

The Pulse Transmitter contains a locking collar located directly below the T-handle. Tighten the hex-shaped collar to prevent the T-handle from moving (walking) while pulsating.

Locator Application Techniques

Two devices are provided for probing the surface with the RD500 Locator. A 14cm (5.5 inch) ground spike is supplied for soft surfaces and a brass hard surface plate is included for hard surfaces such as concrete or tarmac (asphalt). The hard surface plate has concentric recessed channels in its surface that allow it to be positioned such that it lays flat against surfaces.

The RD500 is supplied with high quality headphones that have independent volume adjust­ments on each ear piece. Using non-standard headphones may reduce system performance, create oscillation in the audio output and cause mechanical damage to the headphone jack.

Pinpointing pipe location is difficult without using the meter to measure signal level. It is very difficult for the average person to discern slight variations in audio signal levels. Always adjust the sensitivity so as to maintain a mid-scale meter reading while locating. Typical location accuracy is plus or minus one pipe diameter. Always probe or expose the pipe to confirm the exact location before performing any excavation.

Best location results are obtained by beginning your tracing at least 3 meters (10 feet) from the location where the Pulse Transmitter is connected. The signal levels are normally too strong in the area immediately surrounding the Pulse Transmitter. Alternately, tracing may begin at a known pipe location that is not more than 75 meters (250 feet) down the pipe from the Pulse Transmitter.

The preferred method for tracing pipes is to locate at least two known pipe locations that indicate the heading or direction that the pipe is laid. Readings should be taken along an imaginary line that runs perpendicular to the pipeline. Confirm a peak signal reading by taking additional readings that are equal distances from the peak location. These readings should be lower than the peak reading and approximately equal.

Once the pipe direction is determined, it is possible to quickly trace the pipe along this heading and confirm any changes in direction by periodically taking readings.

Always transport and store your Locator in the carrying case to protect it from damage. If the Locator is allowed to fall over and strike a hard surface it may permanently damage the meter.

Locator and Adapter Kit Details

The Locator kit, sprinkler/ hose bib kit, fire hydrant kit and water meter kit details are supplied for your reference in identifying and maintaining the equipment.


Locator Kit Details


Sprinkler/ Hose Bib Kit Details


Hydrant Standpipe Kit Details



RD500-Tx Electronic Pulse Transmitter Kit



Water Meter Standpipe Kit details