Solar PV Combiner Box Configuration Diagram

Photovoltaic Protection Box – Technical Configuration

System Overview

Product by: Kuangya Electrical Equipment Supply (cnkuangya.com)

The PV Combiner Box is a critical component in solar installations, providing centralized DC protection, monitoring, and connection management for multiple PV strings before feeding into the inverter.

Configuration Diagram

┌─────────────────────────────────────────────────────────────────────┐
│                    PV COMBINER BOX (IP65 Enclosure)                 │
│                        Model: KYDB Series                            │
│                     www.cnkuangya.com                               │
├─────────────────────────────────────────────────────────────────────┤
│                                                                       │
│  ┌─────────────────  INPUT SECTION (DC+/DC-)  ──────────────────┐  │
│  │                                                                 │  │
│  │  String 1:  [+]─┤Fuse gPV 14×85├─┤SPD├─┐                     │  │
│  │                                            │                     │  │
│  │  String 2:  [+]─┤Fuse gPV 14×85├─┤SPD├─┤                     │  │
│  │                                            │                     │  │
│  │  String 3:  [+]─┤Fuse gPV 14×85├─┤SPD├─┤  DC Bus (+)         │  │
│  │                                            │                     │  │
│  │  String 4:  [+]─┤Fuse gPV 14×85├─┤SPD├─┤                     │  │
│  │                                            │                     │  │
│  │  String 5:  [+]─┤Fuse gPV 14×85├─┤SPD├─┤                     │  │
│  │                                            │                     │  │
│  │  String 6:  [+]─┤Fuse gPV 14×85├─┤SPD├─┘                     │  │
│  │                                                                 │  │
│  │  ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─ ─   │  │
│  │                                                                 │  │
│  │  String 1:  [-]─────────────────────┐                         │  │
│  │  String 2:  [-]─────────────────────┤                         │  │
│  │  String 3:  [-]─────────────────────┤  DC Bus (-)             │  │
│  │  String 4:  [-]─────────────────────┤                         │  │
│  │  String 5:  [-]─────────────────────┤                         │  │
│  │  String 6:  [-]─────────────────────┘                         │  │
│  │                                                                 │  │
│  └─────────────────────────────────────────────────────────────────┘  │
│                                                                       │
│  ┌────────────────  PROTECTION SECTION  ─────────────────────────┐  │
│  │                                                                 │  │
│  │   DC Bus (+) ──┤DC Circuit Breaker KYDB-63├─┐                │  │
│  │                     (1500V, 63A)              │                │  │
│  │                                                │                │  │
│  │   ┌──────────────────────────────────────────┘                │  │
│  │   │                                                             │  │
│  │   │    ┌─────────────────────────────────┐                    │  │
│  │   ├────┤  DC Surge Protector (SPD)       │                    │  │
│  │   │    │  Type 1+2, 1500V DC              │                    │  │
│  │   │    │  Imax: 40kA, In: 20kA            │                    │  │
│  │   │    └─────────────────────────────────┘                    │  │
│  │   │                      │                                      │  │
│  │   │                      ├──── PE (Ground)                     │  │
│  │   │                                                             │  │
│  │   │    ┌─────────────────────────────────┐                    │  │
│  │   └────┤  DC Switch Disconnector          │                    │  │
│  │        │  Load Break Switch               │                    │  │
│  │        │  Manual Operation                │                    │  │
│  │        └─────────────────────────────────┘                    │  │
│  │                      │                                          │  │
│  │   DC Bus (-) ───────┴────────────────────────────────────┐    │  │
│  │                                                            │    │  │
│  └────────────────────────────────────────────────────────────────┘  │
│                                                                       │
│  ┌─────────────────  OUTPUT SECTION  ────────────────────────────┐  │
│  │                                                                 │  │
│  │   DC Output (+) ────────────────────→  To Inverter (+)        │  │
│  │                                                                 │  │
│  │   DC Output (-) ────────────────────→  To Inverter (-)        │  │
│  │                                                                 │  │
│  │   PE (Ground)   ────────────────────→  Equipment Ground       │  │
│  │                                                                 │  │
│  └─────────────────────────────────────────────────────────────────┘  │
│                                                                       │
│  ┌─────────────────  MONITORING SECTION  ────────────────────────┐  │
│  │                                                                 │  │
│  │   • Voltage Monitoring (DC+ to DC-)                            │  │
│  │   • Current Monitoring (per string)                            │  │
│  │   • Temperature Sensors                                        │  │
│  │   • SPD Status Indicator (Red Light = Fault)                  │  │
│  │   • Communication Port (RS485/Modbus)                          │  │
│  │                                                                 │  │
│  └─────────────────────────────────────────────────────────────────┘  │
│                                                                       │
└─────────────────────────────────────────────────────────────────────┘

Component Specifications

1. PV String Fuses (gPV Type)

モデル: gPV 14×85 mm
評価: 10A – 30A (depending on string current)
電圧: 1000V / 1500V DC
破断能力: High interrupting rating for DC applications
機能: Overcurrent protection for individual PV strings
特徴: UV-resistant, replaceable modules

2. DC Surge Protection Device (SPD)

タイプ: Type 1+2 Combined
定格電圧: 1500V DC
最大放電電流 (Imax): 40kA (8/20μs)
公称放電電流 (In): 20kA
Protection Level (Up): < 4kV
ステータス表示: Visual indicator window (Red = Failure)
機能: Lightning and surge protection

3. DCサーキットブレーカー

モデル: KYDB-63 Series
定格電流: 16A – 63A
定格電圧: 1000V / 1500V DC
ポール: 2P (Positive and Negative)
破断能力: 10kA – 20kA DC
機能: Overload and short-circuit protection, manual isolation
特徴: Arc extinction technology for DC applications

4. DCスイッチ・ディスコネクター

タイプ: Load Break Switch
評価: Up to 63A, 1500V DC
オペレーション: Manual rotary handle
機能: Safe isolation for maintenance
特徴: Lockable in OFF position, visible contact gap

5. エンクロージャー

素材: Powder-coated steel or UV-resistant plastic
Protection Rating: IP65 (dust-tight, water jet protected)
取り付け: Wall-mount or pole-mount options
Cable Entry: Bottom entry with cable glands
寸法: Customizable based on string quantity

Technical Parameters

パラメータ	仕様
Max Input Strings	6 – 16 (customizable)
システム電圧	1000V / 1500V DC
Max Input Current per String	15A – 20A
Total Output Current	Up to 400A
動作温度	-40°C～+70°C
Altitude	≤ 2000m (standard), higher available
コンプライアンス基準	IEC 60947, IEC 61643-31, CE, RoHS
保証	標準5年

プロテクション機能

✓ 文字列レベルの保護

Each PV string is individually protected with gPV fuses and SPDs, preventing fault propagation between strings.

✓ サージ保護

Type 1+2 SPD provides comprehensive protection against direct and indirect lightning strikes, as well as switching surges.

✓ 過電流保護

DC circuit breakers protect the main bus and downstream equipment from overload and short-circuit conditions.

✓ Isolation Capability

Switch disconnector allows safe maintenance with visible contact separation and lockout capability.

✓ Reverse Polarity Protection

Blocking diodes or fuse coordination prevents reverse current flow during shading or module mismatch.

Installation Guidelines

場所の選択

Install close to PV array to minimize DC cable runs
Ensure adequate ventilation and shade from direct sunlight
Accessible for maintenance and inspection

Wiring Requirements

Use UV-resistant DC cables (PV1-F or equivalent)
Proper cable sizing based on string current and voltage drop
Secure cable glands to maintain IP65 rating

接地

Connect enclosure to equipotential grounding system
Ensure SPD ground lead is as short as possible (< 0.5m)
Use copper grounding conductors (min. 16mm²)

ラベリング

Clear identification of each string input
Warning labels for DC voltage hazards
Operation instructions on enclosure door

メンテナンス・スケジュール

Interval	メンテナンスタスク
毎月	Visual inspection of SPD status indicators
四半期	Check for loose connections, clean enclosure
毎年	Thermal imaging scan, torque verification
As Needed	Replace failed SPDs, blown fuses

Quality Assurance

Kuangya Electrical Commitment:

✓ Factory acceptance testing (FAT) before shipment
✓ IEC, CE, RoHS compliance certification
✓ Rigorous thermal cycling and voltage stress tests
✓ Comprehensive technical documentation
✓ Global technical support and spare parts availability

For detailed specifications, customization, or quotation:

光亜電気設備供給\
ウェブサイト cnkuangya.com\
Product Line: DC Photovoltaic Protection Systems\
Experience: 25+ years | 2000+ projects delivered worldwide

This configuration represents a standard 6-string PV combiner box. Configurations can be customized for 8, 12, 16, or more strings based on project requirements.