Toshiba TOSBERT S7 series frequency converter

Disconnect the power supply for insulation testing every year, and use a 500V megohmmeter to measure the insulation of the main circuit. The insulation of the main circuit to ground should be ≥ 10M Ω, and the insulation of the control circuit should be ≥ 100M Ω

Every 2 years, the capacitance measurement of the DC bus capacitor shows a capacity decay of ≤ 20% (if exceeded, replacement is required)

(2) Regularly replace components (life management)

The core components of the frequency converter have a clear service life and need to be replaced upon expiration:

Component Name Service Life Replacement Standard Recommended Model

Cooling fan operates continuously for 2-3 years with abnormal noise, decreased speed, and no rotation. Toshiba FS-1238, FS-9225

DC bus capacitor with 5-8 years (ambient temperature ≤ 40 ℃) capacity decay>20%, leakage, bulging Toshiba EEU-FR1C102, EEU-FR1C222

Braking resistor: 3-5 years (frequent braking scenario), resistance change>10%, surface carbonization matching according to model (e.g. BR-10 Ω/500W for 15kW model)

The filter screen is severely clogged for 6-12 months, affecting ventilation. Toshiba filter screen FS-FILTER-01

2. Long term shutdown and restart maintenance

Long term shutdown maintenance (≥ 6 months):

Before shutdown: Backup the parameters of the frequency converter (through the panel or software) and clean the internal dust;

Storage period: Power on every 6 months (no load, voltage gradually increases from 0 to rated value for 30 minutes) to activate the capacitor;

Storage environment: Temperature -20 ℃~40 ℃, humidity ≤ 60% RH, no corrosive gases.

Restart maintenance:

Check if the appearance, terminals, and cables of the frequency converter are normal;

Measure the insulation resistance of the main circuit;

Restore backup parameters, conduct a 5-minute no-load trial run, check for any abnormalities, and then run with load.