The Projoy PEAS Series AC Isolator provides the AC-side isolation required at the output of every grid-connected solar PV inverter under BS 7671 (18th Edition) and MCS installation standards. Available in 20A, 25A, 32A and 40A ratings (4-pole), covering single-phase and three-phase inverters from approximately 1.5 kW to 9 kW output. The IP66 polycarbonate enclosure is suitable for outdoor and exposed installations. The rotary handle locks in the OFF position with a padlock for safe isolation during maintenance. Four mounting options: panel mount, DIN rail, door clutch and standalone enclosure. Silver-alloy contacts for low resistance and extended electrical life. Certified to IEC/EN 60947-3. CE and TUV approved. ISO 9001 and ISO 14001 certified manufacture. 20–40A Current Range 4-Pole Configuration IP66 Enclosure 440V AC Max Voltage CE + TUV Certified ISO 9001 Quality ⚠ Qualified Installer Required: AC isolators for grid-connected PV systems must be installed by a suitably qualified and competent person to BS 7671 and MCS standards. Variant Overview — Which Rating Do You Need? Rating Poles Inverter Output (single-phase approx.) Typical System Size 20A 4P Up to ~4.6 kW 1–2 bedroom, ~2–4 kWp 25A 4P Up to ~5.75 kW 2–3 bedroom, ~3–5 kWp 32A 4P Up to ~7.4 kW 3–4 bedroom, ~5–7 kWp 40A 4P Up to ~9.2 kW Larger homes / multi-string, ~6–9 kWp 63A+ 4P Larger 3-phase or higher-output systems PEAS 63–80A series Select the rating at or above the inverter manufacturer's rated maximum AC output current. For 3-phase: divide total inverter output by (400V x 1.732) for per-phase current. Key Features BS 7671-Required AC Isolation for Grid-Connected PV Inverters BS 7671 (18th Edition Amendment 1) requires a lockable means of isolation on the AC output side of every grid-connected PV inverter. This must be separate from the DC isolation provided by the inverter’s internal switch or an external firefighter safety switch. The PEAS is rated and certified to IEC/EN 60947-3 specifically as an isolator-disconnector — exactly the device type referenced in BS 7671 for this purpose. BS 7671 compliantIEC/EN 60947-3Isolator-disconnector rated Lockable in OFF Position — Padlock Compatible The rotary handle can be turned to the OFF position and a standard padlock passed through the hasp to physically prevent re-energisation. This satisfies the Electricity at Work Regulations 1989 requirement for secure isolation during maintenance work on the inverter, wiring or downstream equipment. Clear ON/OFF position markings are provided on the handle and body. Padlock in OFFElectricity at Work RegsClear position marking IP66 — Weatherproof for External and Exposed Installation Enclosure variants carry an IP66 rating — fully dustproof and protected against high-pressure water jets from any direction. Suitable for outdoor meter box mounting, external wall positions alongside the inverter, garages, outbuildings and exposed roof level. Enclosure body is UL 94 V-0 flame-retardant polycarbonate. IP66Outdoor-ratedV-0 polycarbonate Four Mounting Options — Adapts to Any Installation Available in: standalone enclosure (IP66, wall-mounted); panel mount (bolted to enclosure backplate or surface); DIN rail (snap-fit to 35mm DIN rail in a consumer unit); door clutch (handle on door, mechanism on chassis — common for integrated inverter cabinet installations). All use the same switch mechanism. Standalone enclosurePanel mountDIN railDoor clutch Silver-Alloy Contacts — Low Resistance, Long Life Silver-alloy contacts provide lower contact resistance than copper, better arc resistance, and longer rated electrical lifespan under repeated switching. In PV installations where the isolator may carry maximum current for extended periods during peak generation, low contact resistance matters for both efficiency and contact temperature management. Silver-alloy contactsLow contact resistanceLong electrical life CE and TUV Certified — ISO 9001 and ISO 14001 Manufacture The PEAS carries CE and TUV approvals. Projoy Electric holds ISO 9001 quality management and ISO 14001 environmental management system certifications. All products undergo rigorous environmental and electrical testing. Projoy’s full DC isolator range has also obtained UKCA certification for the UK market. CE + TUVUKCA (DC range)ISO 9001 + 14001 Technical Specifications PEAS Series — Electrical Current Ratings Available 20A, 25A, 32A, 40A (this range); 63A, 80A (PEAS 63–80A) Max AC Voltage 440V AC Nominal AC Voltage 230V / 400V AC Number of Poles 4P (standard) Contact Material Silver alloy Physical and Environmental IP Rating (Enclosure) IP66 Flame Retardant UL 94 V-0 (enclosure body) Mounting Options Panel, DIN Rail, Door Clutch, Standalone Enclosure Handle Rotary, lockable in OFF position with padlock Standards and Certifications Test Standard IEC/EN 60947-3 Certifications CE, TUV, ISO 9001, ISO 14001 Additional UKCA (Projoy full DC isolator series) Applications Primary Use AC isolation at PV inverter output — BS 7671 / MCS compliance Secondary Uses Motor control, industrial AC disconnect, emergency isolation Manufacturer Projoy Electric Co. Frequently Asked Questions Where in a solar PV system is the AC isolator installed? Between the inverter AC output and the consumer unit (or AC distribution board). It should be mounted close to the inverter, clearly labelled as a PV AC isolator, and accessible for operation. This is a BS 7671 requirement for all grid-connected PV systems. Which current rating do I need? Select at or above the inverter's maximum rated AC output current. For a 3.6 kW single-phase inverter: 3600 ÷ 230 = 15.7A → use 20A. For a 5 kW inverter: 21.7A → use 25A. For a 7 kW inverter: 30.4A → use 32A. Always verify against the specific inverter datasheet. Is the AC isolator needed if I already have a PEFS-EL firefighter safety switch? Yes. The PEFS-EL handles DC string isolation only. The AC isolator is a separate, independent requirement for the AC output side. BS 7671 and MCS require both — they serve different purposes and different parts of the circuit. What does lockable in the OFF position mean in practice? The rotary handle is turned to OFF, then a padlock is inserted through the hasp on the handle to physically prevent it being rotated back to ON. This provides the secure isolation required by the Electricity at Work Regulations 1989 before working on the inverter or downstream wiring. Is a 4-pole isolator needed for a single-phase system? For single-phase PV, a 2-pole isolator would technically cover L and N, but a 4-pole device is commonly specified because it also isolates the PE (earth) conductor where relevant. Many MCS installers and DNOs specify a 4-pole device as standard practice for unambiguous system isolation. Check your specific DNO and MCS requirements. Related Products Projoy PEFS-EL Firefighter Safety Switch (2-string, 40A FB) DC string rapid shutdown — pairs with this AC isolator Projoy PEFS-EL Firefighter Safety Switch (5-string, 20A) DC string shutdown for mid-size arrays Projoy PEFS-EL Firefighter Safety Switch (10-string, 20A) DC string shutdown for larger arrays Projoy Battery Isolator PEBS-L with Enclosure DC MCB for battery-inverter isolation
