Overload Protection Characteristics - Mitsubishi Electric MELDAS MDS-R Series Technical Specification And Instruction Manual

3-1-2 Overload protection characteristics

The servo drive unit has an electronic thermal relay to protect the servomotor and servo drive unit from
overloads. The operation characteristics of the electronic thermal relay are shown below when standard
parameters (SV021=60, SV022=150) are set.
If overload operation over the electronic thermal relay protection curve shown below is carried out,
overload 1 (alarm 50) will occur. If the maximum current is commanded at 95% or higher continuously
for one second or more due to a machine collision, etc., overload 2 (alarm 51) will occur.
(1) Motor HF44
10000
1000
100
10
1
0.1
0
(2) Motor HF74
10000
1000
100
10
1
0.1
0
3. Characteristics
HF44 Overload protection characteristics
100 200
Current (stall %)
HF74 Overload protection characteristics
100 200
Current (stall %)
3 - 3
When rotating
When stopped
300 400
When rotating
When stopped
300 400
500
500