Installation: Leviton R, P, B, and M Series Surge Protective Devices Instruction Manual

Overview

The R, P, B, and M Series Surge Protective Devices are permanently installed electrical surge protectors designed to reduce the effects of transient overvoltage on service equipment, distribution panels, and connected electrical loads. These SPDs are intended for qualified electricians working on properly grounded commercial, industrial, residential, and other compatible electrical systems.

The product families cover different installation positions and electrical configurations. R and P Series units are Type 1 devices suitable for line-side installation and may also be installed on the load side of the service disconnect. B and M Series units are Type 2 devices intended for load-side installation. Models with UL 1293 filtering are qualified to the applicable standards but are restricted to Type 2 installation.

Correct system voltage, grounding, bonding, enclosure selection, conductor routing, and installation procedures are essential for reliable surge protection. This guide summarizes the practical requirements for using the R, P, B, and M Series Surge Protective Devices.

Specifications

• R2120-B: 120/240 V AC, 60 Hz.
• P2120-B: 120/240 V AC, 60 Hz.
• P3120-YB: 208Y/120 V AC, wye, 60 Hz.
• P3277-YB: 480Y/277 V AC, wye, 60 Hz.
• B1120-B: 120 V AC, 60 Hz.
• B2120-B: 120/240 V AC, 60 Hz.
• B3120-YB: 208Y/120 V AC, wye, 60 Hz.
• B3240-DB: 240 V AC, delta, 60 Hz.
• B3240-HB: 120/240 V AC, high-leg delta, 60 Hz.
• B3277-YB: 480Y/277 V AC, wye, 60 Hz.
• B3347-YB: 600Y/347 V AC, wye, 60 Hz.
• B3480-DB: 480 V AC, delta, 60 Hz.
• M2120-B: 120/240 V AC, 60 Hz.
• M3120-YB: 208Y/120 V AC, wye, 60 Hz.
• M3240-DB: 240 V AC, delta, 60 Hz.
• M3277-YB: 480Y/277 V AC, wye, 60 Hz.
• M3347-YB: 600Y/347 V AC, wye, 60 Hz.
• M3480-DB: 480 V AC, delta, 60 Hz.
• M3600-DB: 600 V AC, delta, 60 Hz.
• Enclosures: R, P, and B Series use NEMA 4X enclosures; M Series uses a NEMA 4 enclosure.
• Operating temperature: R and P Series: -31°F to 185°F (-35°C to 85°C); B and M Series: -40°F to 185°F (-40°C to 85°C).
• Humidity: 0% to 95% relative humidity, noncondensing.
• Short-circuit current rating: 200 kA SCCR for the listed SPDs.
• Suggested breaker connection: 20 A for R, P, and B Series; 30 A for M Series, where applicable to the installation.

Detailed Description

An SPD monitors the connected electrical system and limits transient voltage by diverting surge energy away from protected equipment through the grounding system. The protective components operate during abnormal voltage events and include internal thermal over-temperature protection. The diagnostic system indicates whether the suppression elements remain available.

R and P Series devices are classified as Type 1 SPDs. They can be installed on the line side of the service disconnect overcurrent device or on the load side when permitted by the electrical design. B and M Series devices are Type 2 SPDs and are intended for installation on the load side of the service disconnect overcurrent device.

The connection conductors are identified by function. Black conductors are energized line connections, white is neutral, and green is ground. On delta units, the orange conductor identifies the high leg, which is Phase B. Follow the specific system configuration and device markings when making connections.

Some units include an audible alarm and Form C dry contacts. The alarm and contacts monitor suppression-element status, including a loss of power. The dry-contact leads are white for common, black for normally open, and brown for normally closed operation.

SPD background noise is negligible or absent, so audible operating noise generally does not restrict the installation location. However, installation must still match the enclosure rating and the environmental conditions at the mounting site.

Safety

• Only qualified electricians should install, inspect, or service an SPD.
• Disconnect power before installation or service, then verify that the panel and all relevant conductors are de-energized with suitable test equipment.
• Use appropriate personal protective equipment and electrical safety procedures. Hazardous voltage may be present inside an SPD.
• Do not energize the device until the electrical system is fully installed, inspected, and tested.
• Confirm that the SPD voltage rating and configuration match the electrical distribution system before applying power.
• Verify that the neutral is bonded to ground as required at service equipment and downstream separately derived systems.
• Use an equipment grounding conductor on every circuit connected to the SPD.
• Do not use an SPD intended for grounded systems on an ungrounded system. Ungrounded systems can develop excessive line-to-ground voltage during faults.
• Do not perform high-potential insulation tests or other tests above the SPD’s maximum continuous operating voltage while the SPD remains connected.
• Disconnect the SPD from its power source before elevated-voltage testing. On four-wire systems, disconnect the SPD neutral connection as well.
• Failure to disconnect the device during high-potential testing can damage the suppression components and void the warranty.
• Incorrect neutral-to-ground bonding can produce abnormal voltage, damage the SPD, and void warranty coverage.

Pre-Installation Planning

Inspect the shipping container and the device for visible damage before installation. If damage appears to have occurred during shipping or handling, retain the packaging and follow the appropriate shipping-claim process before placing the unit into service.

Store the SPD in a clean, dry location between -49°F and 140°F (-45°C and 60°C). Protect it from high condensation and prolonged moisture exposure.

Confirm that the enclosure rating suits the installation environment. Consider moisture, dirt, excessive dust, flammable materials, corrosive vapors, and other site conditions before selecting the mounting location. Excessive heat can activate internal thermal protection.

Install the SPD as close as practical to the panel or equipment being protected. Long conductors add parasitic inductance and can reduce clamping performance. Plan for the shortest, straightest possible line, neutral, and ground conductors, and select breaker positions close to the SPD and the panel neutral and ground connections.

When longer conductors cannot be avoided, gently twist the conductors together at approximately one or two twists per foot, or secure them together with tie wraps. Avoid unnecessary loops and sharp routing changes.

When connected on the load side of the main disconnect, a circuit breaker is recommended as the disconnecting means and as short-circuit protection for the connecting conductors. Follow all applicable electrical codes, including requirements addressing surge protective devices.

For a retrofit panel without an available breaker position, applicable code-compliant options may include consolidating loads to free a position or using a properly sized bus tap and a fused safety switch. Any such arrangement must be designed and installed by a qualified electrician in accordance with the governing code.

Setup and Installation

1. Use a voltmeter to measure the available system voltages and confirm that the selected SPD has the correct voltage and wiring configuration.
2. If the device includes dry contacts, plan the control or monitoring wiring before mounting the SPD.
3. Turn off power at the panel and verify that the panel is de-energized.
4. Determine the correct connection points, breaker location, and mounting position.
5. Plan the conductor route so line, neutral, and ground leads remain as short and straight as possible.
6. Remove a knockout sized for the approved wiring method.
7. Mount the SPD securely and use fittings, seals, and wiring methods suitable for the enclosure rating.
8. Connect each conductor to the appropriate system point. Keep all connections short, direct, and properly supported.
9. Identify conductors as needed: black for energized line conductors, white for neutral, green for ground, and orange for the high leg on delta systems.
10. Check system grounding, neutral bonding, conductor terminations, and the absence of faults or hazards before energizing.
11. Restore power and check the operating indicators and any installed options.

Use the closest suitable breaker position whenever possible. The suggested breaker size is 20 A for R, P, and B Series devices and 30 A for M Series devices, subject to the specific installation, conductor ampacity, and applicable code requirements.

Operation and Indicators

LED Status

Green LEDs indicate that complete protection is available. If a metal-oxide varistor suppression stack fails, the LED associated with the affected protection mode turns off. A failed or unlit protection indicator requires prompt investigation by a qualified electrician.

Audible Alarm

The audible alarm sounds when a suppression element reaches a failed condition. It can be silenced only by removing power from the SPD through its breaker. Removing power also leaves the electrical system without the protection provided by that device, so the cause should be addressed promptly.

If the alarm cycles immediately after energizing, turn off power to the SPD and have the installation checked by qualified service personnel.

Dry Contacts

The three 22 AWG dry-contact wires change state when a suppression element reaches end of life or when the SPD loses power. Use these contacts only for low-voltage or control-signal monitoring.

• White: Common.
• Black: Normally open.
• Brown: Normally closed.
• Maximum switching current: 2 A.
• Maximum switching voltage: 240 V AC.

Higher-energy control applications require an additional relay outside the SPD. If the dry contacts are not used, insulate the wire ends, coil the leads, and secure them so they cannot contact energized parts or interfere with the enclosure.

Grounding and Bonding

A dependable grounding system is essential to SPD performance. Use a single-point grounding approach where the service grounding electrode system is bonded to other available electrodes and building grounding paths, such as building steel, metal water piping, and driven rods, where required by the electrical design.

For sensitive electronic and computer equipment, keep grounding impedance as low as practical. If metallic raceway provides an additional grounding path, install an insulated grounding conductor inside the raceway and maintain electrical continuity at every raceway connection.

Do not create a separate isolated ground solely for the SPD. Verify grounding connections and ground-grid continuity during regular electrical maintenance inspections. Four-wire systems require neutral-to-ground bonding through the appropriate main bonding jumper in accordance with applicable code.

Cleaning and Maintenance

These surge protective devices require little routine maintenance. Periodically inspect the LEDs, audible alarm condition, dry-contact status, enclosure, wiring, and mounting hardware. Keep the enclosure clean and free of accumulated dirt or contaminants appropriate to the site conditions.

Before inspecting or cleaning the device, follow the same electrical safety procedure used for service: disconnect power, verify the absence of voltage, and use appropriate protective equipment. Do not open, modify, overload, or alter the SPD.

Troubleshooting

• Green LED is off: The associated protection mode may have failed, or the SPD may not be receiving power. Have a qualified electrician verify the breaker, wiring, system voltage, grounding, and device condition.
• Audible alarm sounds: A suppression element may have reached end of life. The alarm stops only when power is removed, but disconnecting the device removes its protection. Arrange for qualified diagnosis and replacement as needed.
• Alarm cycles after energizing: Turn off power immediately. Check for incorrect voltage, incorrect phase configuration, wiring errors, neutral-bonding problems, or a damaged SPD.
• Dry-contact status indicates a fault: Check whether the SPD has lost power or a suppression element has reached end of life. Inspect the monitoring circuit separately from the power connections.
• Device damage after testing: High-potential testing may have been performed while the SPD remained connected. Disconnect the SPD and its neutral connection on four-wire systems before any future elevated-voltage test.
• Repeated SPD failures: Verify system grounding, neutral-to-ground bonding, voltage rating, enclosure environment, conductor routing, and the suitability of the SPD for a grounded or ungrounded system.

Warranty

The product carries a limited five-year warranty for the original consumer purchaser against defects in materials and workmanship under normal and proper use. The stated remedy is repair or replacement at the manufacturer’s option.

Warranty coverage excludes labor for removal or reinstallation and does not cover improper installation, an unsuitable environment, overloading, misuse, abuse, unauthorized opening or alteration, abnormal operating conditions, or failure to follow product instructions. A separate connected-equipment warranty may apply only to selected SPD catalog numbers.

Pros & Cons

• Pros: Multiple voltage and phase configurations support a wide range of distribution systems.
• Pros: R and P Series Type 1 models can be used on the line side or load side when properly installed.
• Pros: B and M Series Type 2 models support load-side protection, with enclosure options suited to demanding environments.
• Pros: Green status LEDs, audible alarm capability, and optional dry contacts provide useful condition monitoring.
• Pros: NEMA 4X options are available in the R, P, and B families, while M Series devices use NEMA 4 enclosures.
• Cons: Installation requires a qualified electrician and careful compliance with grounding, bonding, voltage, and code requirements.
• Cons: Long or poorly routed conductors can reduce surge-protection performance.
• Cons: Removing power to silence an alarm also removes the protection supplied by the SPD.