Viridian Clearline Solar Inverter | 1.0–6.0kW Single Phase | 1 & 2 MPPT | Integrated DC Isolator
Viridian Clearline Solar Inverter | 1.0–6.0kW Single Phase | 1 & 2 MPPT | Integrated DC Isolator
Single Phase 1 & 2 MPPT 1.0 kW – 6.0 kW Integrated DC Isolator IP65 Rated 10-Year Warranty Viridian Solar
The Viridian Clearline Inverter is an efficient, compact and quiet single-phase string inverter range designed specifically to complement Clearline Fusion roof-integrated solar panels. Eight output sizes from 1.0 kW to 6.0 kW cover residential systems from a handful of panels up to 9.0 kWp, with every model featuring a factory-fitted integrated DC isolator switch, natural convection cooling (no fan — no noise, no moving parts), and a maximum efficiency of up to 97.6%. Models from 1.0–3.0 kW have a single MPPT, ideal for simple unshaded arrays; models from 3.0–6.0 kW have dual MPPT for split or partially shaded arrays. All models are IP65 rated for outdoor or garage installation and carry a 10-year warranty with UK technical and design support from Viridian.
⚠️ WiFi monitoring and export limiting are optional add-ons. The inverter ships without a communication module fitted. Add the VIR-CSI-WIFI (WiFi module) for remote monitoring via the WE Mate app and Solar Portal. Add the VIR-CSI-CT (CT clamp) alongside the WiFi module to enable export power limiting — required if your DNO imposes an export cap.
Variant Selection
| MPN | Output Power | MPPT | Max DC Voltage | MPPT Voltage Range | Start-Up Voltage | Max DC Input | Max Efficiency | Suitable Array Size |
|---|---|---|---|---|---|---|---|---|
| VIR-CSI1000 | 1.0 kW | 1× MPPT | 500 V | 40–450 V | 40 V | 15 A | 97.2% | Up to ~1.5 kWp |
| VIR-CSI1500 | 1.5 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.3% | Up to ~2.25 kWp |
| VIR-CSI2000 | 2.0 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.5% | Up to ~3.0 kWp |
| VIR-CSI2500 | 2.5 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~3.75 kWp |
| VIR-CSI3000 | 3.0 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~4.5 kWp |
| VIR-CSI3600 | 3.6 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~5.4 kWp |
| VIR-CSI5000 | 5.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~7.5 kWp |
| VIR-CSI6000 | 6.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~9.0 kWp |
ℹ️ 1 MPPT vs 2 MPPT: Single-MPPT models (CSI1000–CSI3000) are ideal for simple, unshaded, uniform arrays where all panels face the same direction. Dual-MPPT models (CSI3600–CSI6000) allow two independent strings to be optimised separately — useful for split arrays, different roof pitches or partial shading. Note: the CSI3000 is also available in a dual-MPPT 'D' version (CSI3000D) for split-string applications.
Key Features
- ✓Integrated DC isolator switch factory-fitted on every model — eliminates the need for a separate DC switch enclosure on the array, reducing installation time and cost
- ✓Natural convection cooling — no fan, no moving parts, whisper-quiet operation; reduces maintenance requirements and extends service life
- ✓Low start-up voltage (40–50 V) — begins generating power in low light conditions, maximising daily energy harvest, particularly on Clearline Fusion in-roof arrays with longer cable runs
- ✓High maximum efficiency up to 97.6% — class-leading conversion efficiency across the full range
- ✓IP65 weatherproof rating — suitable for installation in garages, lofts, on external walls, or in meter cupboards
- ✓A4 footprint, lightweight design — discreet and easy to mount on wall bracket; all models within the 1–3 kW range share the same compact housing
- ✓Smart control capability — real-time generation monitoring (requires optional WiFi module VIR-CSI-WIFI) and optional export limiting (requires VIR-CSI-CT CT clamp and WiFi module)
- ✓WE Mate app and Solar Portal monitoring — when WiFi module is fitted, full remote access to live generation data, fault history, firmware updates and parameter adjustment via app or browser
- ✓Optional AFCI (Arc Fault Circuit Interrupter) — available on dual-MPPT models; detects arc faults in DC wiring per IEC 63027 and automatically shuts down for protection
- ✓Bluetooth commissioning built-in — configure and commission the inverter locally via the WE Mate app without needing a WiFi connection at commissioning time
- ✓LCD display and buttons — on-device display for real-time readings and parameter setting without app access
- ✓G99 / G98 grid connection compliant — suitable for connection to UK single-phase grid; supports all required protective functions and grid settings
- ✓Perfectly matched to Clearline Fusion panels — voltage and current specifications optimised for PV16-G1 and PV16-M10 module strings; UK design support available from Viridian
- ✓10-year product warranty — backed by Viridian Solar UK with Cambridge-based technical and design support
Sizing Guide — Which Inverter for My Array?
Quick sizing rule: Select an inverter rated at approximately 80–100% of your total array DC peak power (kWp). For a 3×3 portrait array of PV16-405-M10 panels (9 × 405 W = 3.645 kWp), the CSI3600 or CSI5000 dual-MPPT would be the appropriate choice. For a 2×2 portrait array of PV16-335-G1 (4 × 335 W = 1.34 kWp), the CSI1500 single-MPPT is well-matched. Contact Viridian's UK technical team (01480 839 865) if you need design support.
Technical Specifications
| Specification | Value |
|---|---|
| Manufacturer | Viridian Solar Ltd |
| Model Range | Clearline CSI1000S / CSI1500S / CSI2000S / CSI2500S / CSI3000S (single MPPT) · CSI3600D / CSI5000D / CSI6000D (dual MPPT) |
| Grid Type | Single phase, 230 V AC, 50 Hz (G99/G98 compliant) |
| AC Output Voltage | 220 / 230 / 240 V (configurable) |
| Power Factor | ~1 (adjustable 0.8 cap – 0.8 ind) |
| Protection Class | Class I |
| Overvoltage Category | DC side: OVC II · AC side: OVC III |
| Isolation | Non-isolated (transformerless) |
| IP Rating | IP65 |
| Operating Temperature | –25 °C to +60 °C (power derating above ~45 °C ambient) |
| Cooling | Natural convection — fanless |
| Communication | Bluetooth (built-in) · WiFi / LAN / 4G (optional module, plug-in port) |
| Monitoring App | WE Mate (iOS & Android) · Solar Portal (web browser) |
| Export Limiting | Optional — requires WiFi module (VIR-CSI-WIFI) and CT clamp (VIR-CSI-CT) |
| AFCI | Optional (dual-MPPT models) — IEC 63027 compliant, enabled via WE Mate app |
| Certifications | CE (RED / LVD / EMC / RoHS / WEEE / REACH) |
| Warranty | 10 years from date of installation |
| UK Support | Viridian Solar Ltd, Atlas Building, 68 Stirling Way, Papworth, Cambridge CB23 3GY · Tel: 01480 839 865 |
Installation Notes
- ✓Must be installed by a qualified MCS-registered electrician — grid connection requires compliance with G98 (≤3.68 kW) or G99 (>3.68 kW) engineering recommendations
- ✓Wall-mounted using the supplied mounting plate and 3× expansion bolts — minimum 200mm clearance above and below for convection airflow
- ✓DC cables use the supplied MC4-compatible connectors — do not use third-party connectors; manufacturer not liable for damage from non-supplied connectors
- ✓AC circuit breaker recommended at ≥1.25× rated output current — size according to local wiring regulations (BS 7671 in the UK)
- ✓Surge protection is built-in on both DC and AC sides
- ✓Firmware upgrades available via USB flash drive or remotely via WiFi module and WE Mate app
Frequently Asked Questions
QDo I need a separate DC isolator?
No. Every Clearline Inverter includes a factory-fitted integrated DC isolator switch. This is a significant advantage over many competitor inverters and simplifies installation by eliminating the need for a separate DC switch enclosure on the array.
QCan I monitor generation remotely?
Yes, but only with the optional VIR-CSI-WIFI WiFi module added. Once fitted, the inverter connects to your home router and you can monitor live and historical generation data via the WE Mate app (iOS/Android) or via the Solar Portal web browser interface. Without the WiFi module, monitoring is only possible via the on-device LCD.
QCan I limit export to the grid?
Yes. Export limiting requires both the VIR-CSI-WIFI WiFi module and the VIR-CSI-CT CT clamp. The CT clamp is installed on the grid supply cable in your consumer unit to measure import/export. The limit is set in the WE Mate app under Advanced Settings → Power Limit. This is commonly required when your DNO connection approval specifies a maximum export limit.
QWhat is the difference between the -S and -D model suffixes?
The S suffix (e.g. CSI1000S, CSI3000S) denotes Single MPPT — one independent DC input channel. The D suffix (e.g. CSI3600D, CSI6000D) denotes Dual MPPT — two independent DC input channels allowing two separate strings to be optimised independently. The Shopify MPNs (VIR-CSI1000 through VIR-CSI3000) correspond to the S models; VIR-CSI3600 through VIR-CSI6000 correspond to the D models.
QIs this inverter compatible with battery storage?
No. The Clearline Inverter is a grid-tied PV string inverter only — it does not support battery storage. It converts DC from solar panels to AC for export to the grid or home use. For a system with battery storage, a separate hybrid inverter would be required.
QDoes the inverter work with all Clearline Fusion panel types?
Yes. The Clearline Inverter is designed to be fully compatible with PV16-G1 and PV16-M10 Clearline Fusion solar panels. Viridian's UK technical team can provide system design support to confirm string configuration, cable sizing, and inverter selection for your specific array.
QWhat does AFCI do and do I need it?
Arc Fault Circuit Interruption (AFCI) detects dangerous electrical arcing in the DC wiring — for example from a damaged connector or degraded cable. If arcing is detected, the inverter shuts down automatically. AFCI is available as an optional feature on dual-MPPT models (CSI3000D–CSI6000D) and is disabled by default; it can be enabled via the WE Mate app. It is not currently mandatory under UK wiring regulations but adds an additional layer of fire safety protection.
QWhat grid connection notification do I need?
Inverters rated ≤3.68 kW (CSI1000–CSI3600) can usually be connected under the simplified G98 notification procedure. The CSI5000 and CSI6000 (>3.68 kW) require a full G99 application to your Distribution Network Operator (DNO) before installation. Your MCS-registered installer will handle this as part of the commissioning process.
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Viridian Clearline Solar Inverter | 1.0–6.0kW Single Phase | 1 & 2 MPPT | Integrated DC Isolator
Single Phase 1 & 2 MPPT 1.0 kW – 6.0 kW Integrated DC Isolator IP65 Rated 10-Year Warranty Viridian Solar
The Viridian Clearline Inverter is an efficient, compact and quiet single-phase string inverter range designed specifically to complement Clearline Fusion roof-integrated solar panels. Eight output sizes from 1.0 kW to 6.0 kW cover residential systems from a handful of panels up to 9.0 kWp, with every model featuring a factory-fitted integrated DC isolator switch, natural convection cooling (no fan — no noise, no moving parts), and a maximum efficiency of up to 97.6%. Models from 1.0–3.0 kW have a single MPPT, ideal for simple unshaded arrays; models from 3.0–6.0 kW have dual MPPT for split or partially shaded arrays. All models are IP65 rated for outdoor or garage installation and carry a 10-year warranty with UK technical and design support from Viridian.
⚠️ WiFi monitoring and export limiting are optional add-ons. The inverter ships without a communication module fitted. Add the VIR-CSI-WIFI (WiFi module) for remote monitoring via the WE Mate app and Solar Portal. Add the VIR-CSI-CT (CT clamp) alongside the WiFi module to enable export power limiting — required if your DNO imposes an export cap.
Variant Selection
| MPN | Output Power | MPPT | Max DC Voltage | MPPT Voltage Range | Start-Up Voltage | Max DC Input | Max Efficiency | Suitable Array Size |
|---|---|---|---|---|---|---|---|---|
| VIR-CSI1000 | 1.0 kW | 1× MPPT | 500 V | 40–450 V | 40 V | 15 A | 97.2% | Up to ~1.5 kWp |
| VIR-CSI1500 | 1.5 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.3% | Up to ~2.25 kWp |
| VIR-CSI2000 | 2.0 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.5% | Up to ~3.0 kWp |
| VIR-CSI2500 | 2.5 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~3.75 kWp |
| VIR-CSI3000 | 3.0 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~4.5 kWp |
| VIR-CSI3600 | 3.6 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~5.4 kWp |
| VIR-CSI5000 | 5.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~7.5 kWp |
| VIR-CSI6000 | 6.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~9.0 kWp |
ℹ️ 1 MPPT vs 2 MPPT: Single-MPPT models (CSI1000–CSI3000) are ideal for simple, unshaded, uniform arrays where all panels face the same direction. Dual-MPPT models (CSI3600–CSI6000) allow two independent strings to be optimised separately — useful for split arrays, different roof pitches or partial shading. Note: the CSI3000 is also available in a dual-MPPT 'D' version (CSI3000D) for split-string applications.
Key Features
- ✓Integrated DC isolator switch factory-fitted on every model — eliminates the need for a separate DC switch enclosure on the array, reducing installation time and cost
- ✓Natural convection cooling — no fan, no moving parts, whisper-quiet operation; reduces maintenance requirements and extends service life
- ✓Low start-up voltage (40–50 V) — begins generating power in low light conditions, maximising daily energy harvest, particularly on Clearline Fusion in-roof arrays with longer cable runs
- ✓High maximum efficiency up to 97.6% — class-leading conversion efficiency across the full range
- ✓IP65 weatherproof rating — suitable for installation in garages, lofts, on external walls, or in meter cupboards
- ✓A4 footprint, lightweight design — discreet and easy to mount on wall bracket; all models within the 1–3 kW range share the same compact housing
- ✓Smart control capability — real-time generation monitoring (requires optional WiFi module VIR-CSI-WIFI) and optional export limiting (requires VIR-CSI-CT CT clamp and WiFi module)
- ✓WE Mate app and Solar Portal monitoring — when WiFi module is fitted, full remote access to live generation data, fault history, firmware updates and parameter adjustment via app or browser
- ✓Optional AFCI (Arc Fault Circuit Interrupter) — available on dual-MPPT models; detects arc faults in DC wiring per IEC 63027 and automatically shuts down for protection
- ✓Bluetooth commissioning built-in — configure and commission the inverter locally via the WE Mate app without needing a WiFi connection at commissioning time
- ✓LCD display and buttons — on-device display for real-time readings and parameter setting without app access
- ✓G99 / G98 grid connection compliant — suitable for connection to UK single-phase grid; supports all required protective functions and grid settings
- ✓Perfectly matched to Clearline Fusion panels — voltage and current specifications optimised for PV16-G1 and PV16-M10 module strings; UK design support available from Viridian
- ✓10-year product warranty — backed by Viridian Solar UK with Cambridge-based technical and design support
Sizing Guide — Which Inverter for My Array?
Quick sizing rule: Select an inverter rated at approximately 80–100% of your total array DC peak power (kWp). For a 3×3 portrait array of PV16-405-M10 panels (9 × 405 W = 3.645 kWp), the CSI3600 or CSI5000 dual-MPPT would be the appropriate choice. For a 2×2 portrait array of PV16-335-G1 (4 × 335 W = 1.34 kWp), the CSI1500 single-MPPT is well-matched. Contact Viridian's UK technical team (01480 839 865) if you need design support.
Technical Specifications
| Specification | Value |
|---|---|
| Manufacturer | Viridian Solar Ltd |
| Model Range | Clearline CSI1000S / CSI1500S / CSI2000S / CSI2500S / CSI3000S (single MPPT) · CSI3600D / CSI5000D / CSI6000D (dual MPPT) |
| Grid Type | Single phase, 230 V AC, 50 Hz (G99/G98 compliant) |
| AC Output Voltage | 220 / 230 / 240 V (configurable) |
| Power Factor | ~1 (adjustable 0.8 cap – 0.8 ind) |
| Protection Class | Class I |
| Overvoltage Category | DC side: OVC II · AC side: OVC III |
| Isolation | Non-isolated (transformerless) |
| IP Rating | IP65 |
| Operating Temperature | –25 °C to +60 °C (power derating above ~45 °C ambient) |
| Cooling | Natural convection — fanless |
| Communication | Bluetooth (built-in) · WiFi / LAN / 4G (optional module, plug-in port) |
| Monitoring App | WE Mate (iOS & Android) · Solar Portal (web browser) |
| Export Limiting | Optional — requires WiFi module (VIR-CSI-WIFI) and CT clamp (VIR-CSI-CT) |
| AFCI | Optional (dual-MPPT models) — IEC 63027 compliant, enabled via WE Mate app |
| Certifications | CE (RED / LVD / EMC / RoHS / WEEE / REACH) |
| Warranty | 10 years from date of installation |
| UK Support | Viridian Solar Ltd, Atlas Building, 68 Stirling Way, Papworth, Cambridge CB23 3GY · Tel: 01480 839 865 |
Installation Notes
- ✓Must be installed by a qualified MCS-registered electrician — grid connection requires compliance with G98 (≤3.68 kW) or G99 (>3.68 kW) engineering recommendations
- ✓Wall-mounted using the supplied mounting plate and 3× expansion bolts — minimum 200mm clearance above and below for convection airflow
- ✓DC cables use the supplied MC4-compatible connectors — do not use third-party connectors; manufacturer not liable for damage from non-supplied connectors
- ✓AC circuit breaker recommended at ≥1.25× rated output current — size according to local wiring regulations (BS 7671 in the UK)
- ✓Surge protection is built-in on both DC and AC sides
- ✓Firmware upgrades available via USB flash drive or remotely via WiFi module and WE Mate app
Frequently Asked Questions
QDo I need a separate DC isolator?
No. Every Clearline Inverter includes a factory-fitted integrated DC isolator switch. This is a significant advantage over many competitor inverters and simplifies installation by eliminating the need for a separate DC switch enclosure on the array.
QCan I monitor generation remotely?
Yes, but only with the optional VIR-CSI-WIFI WiFi module added. Once fitted, the inverter connects to your home router and you can monitor live and historical generation data via the WE Mate app (iOS/Android) or via the Solar Portal web browser interface. Without the WiFi module, monitoring is only possible via the on-device LCD.
QCan I limit export to the grid?
Yes. Export limiting requires both the VIR-CSI-WIFI WiFi module and the VIR-CSI-CT CT clamp. The CT clamp is installed on the grid supply cable in your consumer unit to measure import/export. The limit is set in the WE Mate app under Advanced Settings → Power Limit. This is commonly required when your DNO connection approval specifies a maximum export limit.
QWhat is the difference between the -S and -D model suffixes?
The S suffix (e.g. CSI1000S, CSI3000S) denotes Single MPPT — one independent DC input channel. The D suffix (e.g. CSI3600D, CSI6000D) denotes Dual MPPT — two independent DC input channels allowing two separate strings to be optimised independently. The Shopify MPNs (VIR-CSI1000 through VIR-CSI3000) correspond to the S models; VIR-CSI3600 through VIR-CSI6000 correspond to the D models.
QIs this inverter compatible with battery storage?
No. The Clearline Inverter is a grid-tied PV string inverter only — it does not support battery storage. It converts DC from solar panels to AC for export to the grid or home use. For a system with battery storage, a separate hybrid inverter would be required.
QDoes the inverter work with all Clearline Fusion panel types?
Yes. The Clearline Inverter is designed to be fully compatible with PV16-G1 and PV16-M10 Clearline Fusion solar panels. Viridian's UK technical team can provide system design support to confirm string configuration, cable sizing, and inverter selection for your specific array.
QWhat does AFCI do and do I need it?
Arc Fault Circuit Interruption (AFCI) detects dangerous electrical arcing in the DC wiring — for example from a damaged connector or degraded cable. If arcing is detected, the inverter shuts down automatically. AFCI is available as an optional feature on dual-MPPT models (CSI3000D–CSI6000D) and is disabled by default; it can be enabled via the WE Mate app. It is not currently mandatory under UK wiring regulations but adds an additional layer of fire safety protection.
QWhat grid connection notification do I need?
Inverters rated ≤3.68 kW (CSI1000–CSI3600) can usually be connected under the simplified G98 notification procedure. The CSI5000 and CSI6000 (>3.68 kW) require a full G99 application to your Distribution Network Operator (DNO) before installation. Your MCS-registered installer will handle this as part of the commissioning process.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
Single Phase 1 & 2 MPPT 1.0 kW – 6.0 kW Integrated DC Isolator IP65 Rated 10-Year Warranty Viridian Solar
The Viridian Clearline Inverter is an efficient, compact and quiet single-phase string inverter range designed specifically to complement Clearline Fusion roof-integrated solar panels. Eight output sizes from 1.0 kW to 6.0 kW cover residential systems from a handful of panels up to 9.0 kWp, with every model featuring a factory-fitted integrated DC isolator switch, natural convection cooling (no fan — no noise, no moving parts), and a maximum efficiency of up to 97.6%. Models from 1.0–3.0 kW have a single MPPT, ideal for simple unshaded arrays; models from 3.0–6.0 kW have dual MPPT for split or partially shaded arrays. All models are IP65 rated for outdoor or garage installation and carry a 10-year warranty with UK technical and design support from Viridian.
⚠️ WiFi monitoring and export limiting are optional add-ons. The inverter ships without a communication module fitted. Add the VIR-CSI-WIFI (WiFi module) for remote monitoring via the WE Mate app and Solar Portal. Add the VIR-CSI-CT (CT clamp) alongside the WiFi module to enable export power limiting — required if your DNO imposes an export cap.
Variant Selection
| MPN | Output Power | MPPT | Max DC Voltage | MPPT Voltage Range | Start-Up Voltage | Max DC Input | Max Efficiency | Suitable Array Size |
|---|---|---|---|---|---|---|---|---|
| VIR-CSI1000 | 1.0 kW | 1× MPPT | 500 V | 40–450 V | 40 V | 15 A | 97.2% | Up to ~1.5 kWp |
| VIR-CSI1500 | 1.5 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.3% | Up to ~2.25 kWp |
| VIR-CSI2000 | 2.0 kW | 1× MPPT | 500 V | 50–450 V | 50 V | 15 A | 97.5% | Up to ~3.0 kWp |
| VIR-CSI2500 | 2.5 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~3.75 kWp |
| VIR-CSI3000 | 3.0 kW | 1× MPPT | 600 V | 50–550 V | 50 V | 15 A | 97.6% | Up to ~4.5 kWp |
| VIR-CSI3600 | 3.6 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~5.4 kWp |
| VIR-CSI5000 | 5.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~7.5 kWp |
| VIR-CSI6000 | 6.0 kW | 2× MPPT | 600 V | 50–550 V | 50 V | 16 A per MPPT | 97.6% | Up to ~9.0 kWp |
ℹ️ 1 MPPT vs 2 MPPT: Single-MPPT models (CSI1000–CSI3000) are ideal for simple, unshaded, uniform arrays where all panels face the same direction. Dual-MPPT models (CSI3600–CSI6000) allow two independent strings to be optimised separately — useful for split arrays, different roof pitches or partial shading. Note: the CSI3000 is also available in a dual-MPPT 'D' version (CSI3000D) for split-string applications.
Key Features
- ✓Integrated DC isolator switch factory-fitted on every model — eliminates the need for a separate DC switch enclosure on the array, reducing installation time and cost
- ✓Natural convection cooling — no fan, no moving parts, whisper-quiet operation; reduces maintenance requirements and extends service life
- ✓Low start-up voltage (40–50 V) — begins generating power in low light conditions, maximising daily energy harvest, particularly on Clearline Fusion in-roof arrays with longer cable runs
- ✓High maximum efficiency up to 97.6% — class-leading conversion efficiency across the full range
- ✓IP65 weatherproof rating — suitable for installation in garages, lofts, on external walls, or in meter cupboards
- ✓A4 footprint, lightweight design — discreet and easy to mount on wall bracket; all models within the 1–3 kW range share the same compact housing
- ✓Smart control capability — real-time generation monitoring (requires optional WiFi module VIR-CSI-WIFI) and optional export limiting (requires VIR-CSI-CT CT clamp and WiFi module)
- ✓WE Mate app and Solar Portal monitoring — when WiFi module is fitted, full remote access to live generation data, fault history, firmware updates and parameter adjustment via app or browser
- ✓Optional AFCI (Arc Fault Circuit Interrupter) — available on dual-MPPT models; detects arc faults in DC wiring per IEC 63027 and automatically shuts down for protection
- ✓Bluetooth commissioning built-in — configure and commission the inverter locally via the WE Mate app without needing a WiFi connection at commissioning time
- ✓LCD display and buttons — on-device display for real-time readings and parameter setting without app access
- ✓G99 / G98 grid connection compliant — suitable for connection to UK single-phase grid; supports all required protective functions and grid settings
- ✓Perfectly matched to Clearline Fusion panels — voltage and current specifications optimised for PV16-G1 and PV16-M10 module strings; UK design support available from Viridian
- ✓10-year product warranty — backed by Viridian Solar UK with Cambridge-based technical and design support
Sizing Guide — Which Inverter for My Array?
Quick sizing rule: Select an inverter rated at approximately 80–100% of your total array DC peak power (kWp). For a 3×3 portrait array of PV16-405-M10 panels (9 × 405 W = 3.645 kWp), the CSI3600 or CSI5000 dual-MPPT would be the appropriate choice. For a 2×2 portrait array of PV16-335-G1 (4 × 335 W = 1.34 kWp), the CSI1500 single-MPPT is well-matched. Contact Viridian's UK technical team (01480 839 865) if you need design support.
Technical Specifications
| Specification | Value |
|---|---|
| Manufacturer | Viridian Solar Ltd |
| Model Range | Clearline CSI1000S / CSI1500S / CSI2000S / CSI2500S / CSI3000S (single MPPT) · CSI3600D / CSI5000D / CSI6000D (dual MPPT) |
| Grid Type | Single phase, 230 V AC, 50 Hz (G99/G98 compliant) |
| AC Output Voltage | 220 / 230 / 240 V (configurable) |
| Power Factor | ~1 (adjustable 0.8 cap – 0.8 ind) |
| Protection Class | Class I |
| Overvoltage Category | DC side: OVC II · AC side: OVC III |
| Isolation | Non-isolated (transformerless) |
| IP Rating | IP65 |
| Operating Temperature | –25 °C to +60 °C (power derating above ~45 °C ambient) |
| Cooling | Natural convection — fanless |
| Communication | Bluetooth (built-in) · WiFi / LAN / 4G (optional module, plug-in port) |
| Monitoring App | WE Mate (iOS & Android) · Solar Portal (web browser) |
| Export Limiting | Optional — requires WiFi module (VIR-CSI-WIFI) and CT clamp (VIR-CSI-CT) |
| AFCI | Optional (dual-MPPT models) — IEC 63027 compliant, enabled via WE Mate app |
| Certifications | CE (RED / LVD / EMC / RoHS / WEEE / REACH) |
| Warranty | 10 years from date of installation |
| UK Support | Viridian Solar Ltd, Atlas Building, 68 Stirling Way, Papworth, Cambridge CB23 3GY · Tel: 01480 839 865 |
Installation Notes
- ✓Must be installed by a qualified MCS-registered electrician — grid connection requires compliance with G98 (≤3.68 kW) or G99 (>3.68 kW) engineering recommendations
- ✓Wall-mounted using the supplied mounting plate and 3× expansion bolts — minimum 200mm clearance above and below for convection airflow
- ✓DC cables use the supplied MC4-compatible connectors — do not use third-party connectors; manufacturer not liable for damage from non-supplied connectors
- ✓AC circuit breaker recommended at ≥1.25× rated output current — size according to local wiring regulations (BS 7671 in the UK)
- ✓Surge protection is built-in on both DC and AC sides
- ✓Firmware upgrades available via USB flash drive or remotely via WiFi module and WE Mate app
Frequently Asked Questions
QDo I need a separate DC isolator?
No. Every Clearline Inverter includes a factory-fitted integrated DC isolator switch. This is a significant advantage over many competitor inverters and simplifies installation by eliminating the need for a separate DC switch enclosure on the array.
QCan I monitor generation remotely?
Yes, but only with the optional VIR-CSI-WIFI WiFi module added. Once fitted, the inverter connects to your home router and you can monitor live and historical generation data via the WE Mate app (iOS/Android) or via the Solar Portal web browser interface. Without the WiFi module, monitoring is only possible via the on-device LCD.
QCan I limit export to the grid?
Yes. Export limiting requires both the VIR-CSI-WIFI WiFi module and the VIR-CSI-CT CT clamp. The CT clamp is installed on the grid supply cable in your consumer unit to measure import/export. The limit is set in the WE Mate app under Advanced Settings → Power Limit. This is commonly required when your DNO connection approval specifies a maximum export limit.
QWhat is the difference between the -S and -D model suffixes?
The S suffix (e.g. CSI1000S, CSI3000S) denotes Single MPPT — one independent DC input channel. The D suffix (e.g. CSI3600D, CSI6000D) denotes Dual MPPT — two independent DC input channels allowing two separate strings to be optimised independently. The Shopify MPNs (VIR-CSI1000 through VIR-CSI3000) correspond to the S models; VIR-CSI3600 through VIR-CSI6000 correspond to the D models.
QIs this inverter compatible with battery storage?
No. The Clearline Inverter is a grid-tied PV string inverter only — it does not support battery storage. It converts DC from solar panels to AC for export to the grid or home use. For a system with battery storage, a separate hybrid inverter would be required.
QDoes the inverter work with all Clearline Fusion panel types?
Yes. The Clearline Inverter is designed to be fully compatible with PV16-G1 and PV16-M10 Clearline Fusion solar panels. Viridian's UK technical team can provide system design support to confirm string configuration, cable sizing, and inverter selection for your specific array.
QWhat does AFCI do and do I need it?
Arc Fault Circuit Interruption (AFCI) detects dangerous electrical arcing in the DC wiring — for example from a damaged connector or degraded cable. If arcing is detected, the inverter shuts down automatically. AFCI is available as an optional feature on dual-MPPT models (CSI3000D–CSI6000D) and is disabled by default; it can be enabled via the WE Mate app. It is not currently mandatory under UK wiring regulations but adds an additional layer of fire safety protection.
QWhat grid connection notification do I need?
Inverters rated ≤3.68 kW (CSI1000–CSI3600) can usually be connected under the simplified G98 notification procedure. The CSI5000 and CSI6000 (>3.68 kW) require a full G99 application to your Distribution Network Operator (DNO) before installation. Your MCS-registered installer will handle this as part of the commissioning process.
