ProSLS

Brief Description (summary / meta)

Raycap ProSLS is an end-of-life indicator that continuously monitors the leakage current of a Surge Protective Device (SPD). Leakage current is the most accurate indicator of an SPD's end-of-life status. Using the measured current, ProSLS predicts advanced SPD degradation and communicates this information to the user. It automatically adapts to all SPD sizes and models, operates with a replaceable battery, and offers a remote contact output.

Overview

Surge Protective Devices (SPDs) do not fail instantly — they degrade gradually. Each surge leaves a small change in the varistor's structure. This degradation begins long before the green/red flag indicator on the device's front panel is activated. Traditional indicators only warn after a failure has occurred; at that point, protection is already lost.

ProSLS uses a different approach: leakage current measurement. As a varistor degrades, its continuous leakage current increases. This is the most accurate indicator of an SPD's end-of-life status — and it is a measurable quantity before failure.

The device continuously monitors leakage current. It can measure currents as low as 100 µA. If the leakage current remains at or above 5 mA for 1 hour, the ProSLS issues an SPD degradation alarm. This allows the SPD to be replaced as part of planned maintenance before it fails — ensuring uninterrupted protection.

Automatically adapts to all SPD sizes and models — no separate adjustment is required for SPDs from different manufacturers or types.

The device has a 1 A / 45 V AC / 30 V DC rated remote contact output — information can be directly transferred to a PLC or SCADA system. The front panel features a status indicator and a hard reset button; separate L1, L2, L3 indicators are provided for three phases.

The leakage current sensor is clamped around the conductor; cable diameters up to 12 mm are supported. A 1 m sensor cable provides installation flexibility.

Powered by a replaceable 3.6 V (ER AA) battery — battery life is up to two years. It is 35 mm DIN rail mountable and 2 TE wide. Operating temperature is -30 °C … +70 °C.

The product complies with IEC/EN 61326-1 standard; it is RoHS and CE certified.

Features

• Continuously monitors the leakage current of an SPD
• Predicts advanced degradation using measured current and notifies the user
• Automatic adaptation to all SPD sizes and models
• Lowest measurable current: 100 µA
• SPD degradation alarm: ≥ 5 mA, for 1 hour
• Remote contact output: 1 A / 45 V AC / 30 V DC
• Separate indicators for three phases (L1, L2, L3)
• Hard reset button
• Replaceable battery — 3.6 V (ER AA), up to 2 years life
• Max. cable diameter through sensor: 12 mm
• Sensor cable: 1 m
• 35 mm DIN rail mounting (EN 60715)
• Compact size: DIN 43880 2 TE
• Protection class: IP 20
• Housing: UL 94 V-0 flame retardant thermoplastic
• Operating temperature: -30 °C … +70 °C
• Standard: IEC/EN 61326-1
• Certifications: RoHS, CE

Technical data

ProSLS is used in installations where SPDs must be replaced before failure:

• LV distribution panels — SPD end-of-life monitoring
• Predictive maintenance programs — Planned replacement before failure
• Critical infrastructure facilities — Hospitals, data centers, substations
• Installations requiring uninterrupted protection — Where loss of protection is unacceptable
• Industrial facilities — Factory and production panels
• Solar power plants (SPPs) — Monitoring SPD degradation
• Wind Power Plants — High Strike Activity Sites
• Telecom base stations — Remote and hard-to-reach locations
• High lightning activity regions — Installations expecting rapid degradation
• Remotely monitored facilities — SCADA/PLC integration with RC contact
• Three-phase systems — With separate L1, L2, L3 indicators
• Facilities with different SPD brands/models — With automatic adaptation feature
• Retrofitting existing panels — Sensor clamped around conductor

• ProSLS Datasheet Download
• ProGrid Surge Monitoring Catalog Download