Справочник Пользователя для Mitsubishi Electronics MDS-R

 
 
 

 

 

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When installing an earth leakage breaker, select the breaker on the following basis to prevent the 
breaker from malfunctioning by the higher frequency earth leakage current generated in the servo drive 
unit. 

Obtaining the earth leakage current for all drive units referring to the following table, select an earth 
leakage breaker within the "rated non-operation sensitivity current". 
Usually use an earth leakage breaker for inverter products that function at a leakage current within 
the commercial frequency range (50 to 60Hz). 
If a product sensitive to higher frequencies is used, the breaker could malfunction at a level less 
than the maximum earth leakage current value. 
 

 

 

 

 

1mA 2mA 

1mA 

4mA (for two axes) 

(Note1)  Maximum earth leakage current: Value that considers wiring length and grounding, etc.  

(Commercial frequency 50/60Hz) 

 
 

When actually measuring the earth leakage current, use a product that is not easily affected by the 
higher frequency earth leakage current. The measurement range should be 50 to 60Hz. 

 

 

 

1.  The earth leakage current tends to increase as the motor capacity increases. 
2.  A higher frequency earth leakage current will always be generated because the 

inverter circuit in the drive unit switches the transistor at high speed. Always 
ground to reduce the higher frequency earth leakage current as much as 
possible. 

3.  An earth leakage current containing higher frequency may reach approx. 

several hundreds of mA. According to IEC479-2, this level is not hazardous to 
the human body. 

4.  For safety, ground the machine with Class C (former class 3) grounding.