Detailed Compatibility Selection Table for Frequency Converters & Leakage Protectors
| Application Scenario | Frequency Converter Specification | Recommended Leakage Protector Parameters | Installation & Wiring Requirements | Matching Accessories & Calculation Examples | Key Notes |
|---|---|---|---|---|---|
| Civil/Small Equipment
(e.g., laboratory motors, household inverter air conditioners) |
– Power: ≤ 5.5kW
– Carrier frequency: 2–8kHz – Typical model: INVT GD200A-2R2G-4 – Input current: 10A (for GD200A-2R2G-4) |
– Type: Type A (compliant with IEC 60755 standard)
– Leakage Operating Current (IΔn): 30mA – Operating Time (tΔ): ≤ 0.1s – Rated Current (In): 1.2×10A = 12A (select 16A grade) – Brand recommendation: Siemens 5SU1 16A/30mA/A |
– Install on the input side (between the MCCB and converter input filter)
– Maintain a spacing of ≥ 15cm between input and output cables; do not bundle them – Grounding resistance ≤ 10Ω (civil standard) – Use a 2.5mm² multi-strand copper ground wire |
– Accessories: Input EMC filter (small-capacity, ≤0.1μF)
– Leakage calculation (for general products): IΔn ≥ 10×(Ig1+Ign+3×(Ig2+Igm)) Example: Ig1=0.11mA, Ign=0mA, Ig2=1.32mA, Igm=0.36mA → IΔn≥10×(0.11+0+3×1.68)=51.5mA (select a 30mA Type A anti-harmonic model) |
– Prioritize personal safety; AC-type protectors are forbidden (false tripping rate >80%)
– Refer to the INVT GD200A series manual |
| General Industrial Equipment
(e.g., small pumps, fans) |
– Power: 5.5kW ~ 37kW
– Carrier frequency: 5–10kHz – Typical model: Mitsubishi FR-D700-15K-CHT – Input current: 32A (for 15kW/380V) |
– Type: Type B (anti-harmonic/surge-resistant)
– IΔn: 50–100mA – tΔ: ≤ 0.1s – In: 1.5×32A = 48A (select 63A grade) – Brand recommendation: Mitsubishi NV-C 63A/100mA/B |
– Route input and output cables through separate steel conduits with a spacing of ≥30cm
– Grounding resistance ≤4Ω (industrial standard) – Ground wire cross-section: 4mm² (matches 63A rated current) – Keep the distance between the leakage protector and converter ≤5m |
– Accessories: Input EMC filter + DC reactor
– Leakage calculation (for anti-harmonic products): IΔn ≥10×(Ig1+Ign+Igi+Ig2+Igm) Example: Ig1=0.15mA, Ign=0.5mA, Igi=1.2mA, Ig2=2.1mA, Igm=0.8mA → IΔn≥10×4.75=47.5mA (select 50mA) |
– Type A is acceptable for simple scenarios (compatibility rate: 70%)
– Do not connect contactors in series between the converter and protector |
| Heavy-Duty Industrial Equipment
(e.g., large pumps, compressors) |
– Power: 37kW ~ 110kW
– Carrier frequency: 8–12kHz – Typical model: INVT GD200A-055G-4 – Input current: 180A (for 55kW/380V) |
– Type: Type B (high-frequency compatible)
– IΔn: 100–200mA – tΔ: 0.1–0.2s – In: 1.5×180A = 270A (select 315A grade) – Brand recommendation: Fuji EG315B 200mA/B |
– Install an input EMC filter + output reactor (to suppress capacitive current)
– Adopt a unified grounding system (the converter, motor, and protector share the same ground electrode) – Ground cable shielding at both ends (for cables >30m) |
– Accessories: dV/dt filter (if the output cable exceeds 50m)
– Matching MCCB: 315A (1.5×input current), fast fuse: 200A – Leakage calculation: IΔn≥10×(0.3+1.2+2.5+3.8+1.5)=93mA (select 100mA) |
– Installation on the output side is prohibited (false tripping rate >30%)
– Refer to CSDN harmonic suppression guidelines |
| Large-Scale Units
(e.g., converters >110kW, multi-motor systems) |
– Power: >110kW
– Carrier frequency: 5–10kHz – Typical model: INVT GD200A-160G-4 – Input current: 400A (for 160kW/380V) |
– Type: Type B (high-current grade)
– IΔn: 200–300mA – tΔ: 0.2–0.5s – In: 1.5×400A = 600A (select 630A grade) – Brand recommendation: ABB GS201 630A/300mA/B |
– Equip each converter with an independent leakage protector
– For multi-motor configurations: Install a thermal relay for each motor (e.g., 80A for a 37kW motor) – Grounding resistance ≤4Ω, ground wire cross-section ≥16mm² |
– Accessories: Input filter + AC reactor (to suppress harmonic superposition)
– Leakage calculation for 3-motor parallel setup: IΔn≥10×(0.5×3 + 2.0 + 3.0 + 4.5×3 + 2.0×3)=320mA (select 300mA) |
– Do not share one protector for multiple converters
– Limit the distance between the protector and converter to ≤8m |
| Special Working Condition 1: Long Cable (Output >50m) | – Any power (e.g., 37kW, cable length=80m)
– Carrier frequency: 8kHz – Input current: 80A (for 37kW/380V) |
– Type: Type B
– IΔn: ≥100mA – tΔ: 0.1s – In: 1.5×80A=120A (select 125A grade) |
– Install a dV/dt filter on the motor side (to suppress capacitive current)
– Ground cable shielding at both ends – Maintain a spacing of ≥50cm between input and output cables |
– Capacitive current suppression: A dV/dt filter reduces cable-to-ground capacitive current by 60%
– Leakage calculation: IΔn≥10×(0.2+0.8+1.8+3.2+1.0)=70mA (select 100mA due to the long cable) |
– For cable lengths >100m: Increase IΔn to 150mA
– Refer to McKenna’s long-cable solution |
| Special Working Condition 2: High-Frequency (Carrier >10kHz) | – Any power (e.g., 22kW, carrier=12kHz)
– Input current: 63A (for 22kW/380V) |
– Type: Type B (high-frequency compatible)
– IΔn: 50–100mA – tΔ: 0.1s – In: 1.5×63A=94.5A (select 100A grade) |
– Reduce the carrier frequency to 5–8kHz (if motor noise is acceptable)
– Install an EMC filter (with a common-mode inductor) on the input side – Grounding resistance ≤4Ω |
– Harmonic suppression: An EMC filter reduces 3rd/5th harmonics by 40–50%
– Leakage calculation: IΔn≥10×(0.18+0.6+1.5+2.8+0.9)=60mA (select 63mA) |
– Type A is incompatible (harmonic tolerance <10kHz)
– Refer to the Mitsubishi FR-D700 series guide |
Supplementary Technical Guidelines
1. Leakage Current Calculation Formula (Mandatory for Accurate Selection)
| Product Type | Calculation Formula | Parameter Definition |
|---|---|---|
| General Leakage Protector | IΔn ≥ 10×[Ig1 + Ign + 3×(Ig2 + Igm)] | – Ig1: Line leakage current (mA)
– Ign: Input filter leakage current (mA, 0 if no filter is installed) – Ig2: Line leakage current during power-frequency operation (mA) – Igm: Motor leakage current (mA) |
| Anti-Harmonic/Surge Protector | IΔn ≥ 10×(Ig1 + Ign + Igi + Ig2 + Igm) | – Igi: Frequency converter main unit leakage current (mA, typically 1–3mA for 10–50kW models)
– Other parameters are the same as above |
2. Model Matching Examples (Brand-Specific)
| Frequency Converter Model | Recommended Leakage Protector Model | Matching MCCB/Fuse | Application Scenario |
|---|---|---|---|
| INVT GD200A-0R7G-4 (0.75kW) | Siemens 5SU1 6A/30mA/A | MCCB: 4A, Fuse: 5A | Laboratory small motor |
| Mitsubishi FR-E700-7.5K-CHT (7.5kW) | Mitsubishi NV-S 20A/50mA/B | MCCB: 25A, Fuse: 35A | Small fan/pump |
| ABB ACS580-01-07A3-4 (3kW) | ABB GS201 16A/30mA/A | MCCB: 10A, Fuse: 10A | Civil inverter air conditioner |
| INVT GD200A-400G-4 (400kW) | Fuji SG1000 1000A/300mA/B | MCCB: 1000A, Fuse: 1200A | Large industrial compressor |
3. Prohibited Configurations & Troubleshooting
| Prohibited Operation | Risk Consequence | Troubleshooting for Common Faults |
|---|---|---|
| Using an AC-type leakage protector | False tripping rate >80% (due to harmonic interference) | Frequent false tripping: 1. Replace with Type A/B → 2. Increase IΔn → 3. Check cable separation |
| Installing the protector on the output side | False tripping during operation; protector ineffectiveness | No tripping on ground fault: 1. Relocate to the input side → 2. Reduce grounding resistance → 3. Replace the damaged protector |
| Sharing one protector for multiple converters | Harmonic superposition → leakage current overload | Protector overheating: 1. Replace with a model with a larger In grade → 2. Tighten terminals → 3. Add an input filter |
| Connecting contactors/relays in series between the converter and protector | Inrush current → false tripping | Unstable operation: 1. Remove the series contactor → 2. Shorten the distance between the protector and converter → 3. Adjust the carrier frequency |