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Product Spotlight

Thru-Door Voltage Indicator

18th June 2018       Automation, Controls & Motion Division

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Thru-Door Voltage Indicator

Flashing and Non-Flashing

Catalog Numbers

R-3W / R-3W-SR

SafeSide thru-door voltage indicators provide electrical safety information while the panel doors are safely closed. This “one-size-fits-all” solution detects 3-phase AC or DC voltage from 40-750VAC/30-1000VDC. The encapsulated construction and redundant circuit design means rugged reliability. SafeSide products are available with flashing LEDs (R-3W) and non-flashing LEDs (R-3W-SR).

Safer Lock-Out Tag-Out (LOTO):

Keeping personnel away from live voltage is foundational to electrical safety. Electrical safety demands a precise answer to the question 'Is voltage present?'. Thru-door voltage indicators provide visibility of voltage from outside the enclosure without exposing personnel to voltage.

More Productivity in Mechanical LOTO:

Workers performing mechanical LOTO must isolate electrical energy. An externally-mounted voltage detector provides a means to check voltage inside an electrical panel. Without a voltage indicator, a mechanic performing mechanical LOTO would be required to work in tandem with an electrician using a voltmeter to physically verify voltage inside an electrical panel. In this case, the electrician is exposed to voltage. With thru-door voltage detectors, the mechanic can verify zero electrical energy without any exposure to voltage.

Reduced Voltage Exposure and Arc Flash Risk:

Voltage is the common denominator in an electrical accident or an arc flash; no voltage means no accident, no arc flash. While performing electrical LOTO with a thru-door voltage detector installed, the electrician can pre-check the internal voltage state without opening the enclosure. Next, the electrician should replicate a zero voltage reading with his voltmeter as per NFPA 70e 120.1(5). This low-cost, redundant voltage-verification task reduces arc flash risk and increases electrical safety for workers.

Voltage Indicator
with Solid-on LEDs or Flashing LEDs


    • Redundant Circuitry / Long Life LED's
    • 40-750VAC / 30-1000VDC / 35-600VAC 1Ø
    • Potted Construction with 6' Leads
    • Phase Insensitive
    • 30mm Pushbutton or Pilot Hole
    • High Surge Immunity
    • UL Listed, Type 4X, 12, 13

    • Circuit Breaker Disconnects - No Visible Blades
    • High Energy Panels (NFPA 70E Category 3 or 4
    • Frequently Accessed Panels
    • Mechanical LOTO: Indicating Zero Energy
    • Panels with Multiple Power Sources
  •  Buy Now

Three Phase 40-750VAC/30-1000VDC UL-Listed Voltage Indicator for Type 4X/12/13 for 30mm Mounting

  • R-3W Flashing
    R-3W-KB1 Flush Mount Assembly with Bezel and R-3W (UL)
    R-3W-L Adhesive-Backed Warning Label (slips over installed R-3W)
    R-3W-KB-L Adhesive-Backed Warning Label (slips over installed R-3W-KB)
  • R-3W-SR2 Non-Flashing
    R-3W-SR-KB1 Flush Mount Assembly with Bezel and R-3W-SR (UL)
    R-3W-SR-L Adhesive-Backed Warning Label (slips over installed R-3W-SR)
    R-3W-KB-L Adhesive-Backed Warning Label (slips over installed R-3W-SR-KB)
  • R-3W23 Hazardous Location Flashing Voltage Indicator
    R-3W2-KB1 Flush Mount Assembly with Bezel and R-3W2 (UL)
    R-3W-L Adhesive-Backed Warning Label (slips over installed R-3W2)
    R-3W-KB-L Adhesive-Backed Warning Label (slips over installed R-3W2-KB)

Voltage Indicator


OPERATIONAL RANGE AC Single or 3-Phase: 40-750V 50/60Hz Operates up to 400 Hz
MAXIMUM VOLTAGE: 750VAC/1000VDC - Surge 4300V for 5 seconds
POWER CONSUMPTION: 1.2 Watts @ 750 VAC (Approximately)
TEMPERATURES: Operate: -20ºC to +55ºC, Storage: -45ºC to +85ºC
FAILURE CURRENT: Maximum single component failure fault current is 3.7mA @ 750 3-Phase
FUSING: Follow all Local, State, and national Electrical Codes when installing this equipment. Overcurrent protection of the supply leads may be necessary. The installation of overcurrent protection shall be in accordance with the requirements in the NEC (NFPA 70) or end product standard(s) when used in the final installation.
3-PHASE LINE-TO-LINE <29 30 120 240 480 600 750
FLASHES/SEC (TYPICAL) 0 1.3 4.2 5.8 7.3 8 8.8
DC OR STORED ENERGY (VDC) <27 30 48 110 300 600 1000
FLASHES/SEC (TYPICAL) 0 1.6 2.5 4.5 6.9 8.8 9.1

EVSE Accessories

New! Bezel-mount Installation for Voltage Indicator!

Create a near-flush look by purchasing your Voltage Indicatorwith our new bezel.

Part Number Description
R-3W-KB Flashing Voltage Indicator with Bezel
R-3W-SR-KB Non-Flashing Voltage Indicator with Bezel
R-3W2-KB Class 1 Div 2 Voltage Indicator with Bezel

*Corresponding label available for bezel-mount configurations. Note: When mounting the Bezel (part numbers with -KB), the diameter of the cut-out is as follows: 1.701 inches (43.21mm)

  • Dimensions of the Bezel - Diameter: 2.25”
  • Outside cabinet depth: .20”
  • Inside cabinet depth: 3.50”

Voltage Indicator Alert Label

Leviton provides an integrated approach for tracking, monitoring, and verifying electrical consumption and implementing cost and carbon footprint reduction. With the addition of precise energy measurement and verification systems, Leviton customers have an integrated solution for achieving their sustainability goals.

Part Number Description
R-3W-L Label for Flashing and Class 1 Div 2 Voltage Indicator
R-3W-SR-L Label for Non-Flashing Voltage Indicator
R-3W-KB-L Label for all Bezel Units
  • Label dimensions are 3"W x 2.3"H.

Part #: R-3W-NPT125

A 30mm to 1 ” NPT conduit adapter. This assembly fits into a standard conduit LB for mounting on the outside of an enclosure

Part #: R-3W-DR-C6

Use this door mount accessory for additional voltage protection. Includes a 30mm adapter and 6' of NW10 flexible conduit. (Allow 4.5" depth into panel).

Safe Side Voltage Indicator

Need help choosing the right voltage indicator for your application? One of our sales representatives work with you to find the most suitable solution. Contact us now.

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Thru-Door Voltage Indicator

Thru-Door Voltage Indicator

SafeSide thru-door voltage indicators from Grace Engineered come in “one-size-fits-all” solution, which detects 3-phase AC or DC voltage from 40-750VAC/30-1000VDC for electrical safety information while the panel doors are safely closed.

Read More