
Operating Instructions – Explosion-Proof AC Motors DR63/eDR63, DVE250/280
39
6
Safe operation of motors in category 3
Duty Types and Limit Values
6.3
Safe operation of motors in category 3
Project planning is the basic requirement for safe operation of explosion-proof motors.
The following points have to be considered:
• Adhere to the thermal torque limit characteristic curve
• Observe the dynamic limit torque
• Observe the motor limit frequency
• Select the suitable frequency inverter
• Check the overhung and axial loads on the motor shaft of stand-alone motors
• Observe the maximum gear unit input speed, see n
emax
on the nameplate
• Observe the maximum gear unit output torque, see M
amax
on the nameplate
6.3.1
Maximum permitted torques
The thermal torque limit characteristic curve shows the permitted maximum torque for
continuous operation.
The values may be exceeded for brief periods if the effective operating point lies below
the thermal limit characteristic curve.
The maximum dynamic limit torque of motors of category 3 must not exceed 200% of
M
N
.
Permitted
frequencies
Observe the maximum frequencies listed in the assignment tables for the motor/
frequency inverter combinations. These values must not be exceeded.
Frequency inverter
selection
Base your selection of the appropriate frequency inverter on the table in chapter
"Motor/inverter assignment": MOVIDRIVE
®
and MOVITRAC
®
".
6.3.2
Motor/inverter assignment: MOVIDRIVE
®
and MOVITRAC
®
Motor type II3GD
motor connection
motor connection
P
FI
[kW]
n
max
[rpm]
P
FI
[kW]
n
max
[rpm]
DR63S4
0.25
1)
1) Only MOVITRAC
®
B
2100
0.25
3600
DR63M4
2100
0.25
3600
DR63L4
2100
0.37
3600
DVE250M4
55
2100
(90)
2)
, 110
3)
2) Values in brackets: optional
3) Only MOVIDRIVE
®
B
2500
DVE280S4
75
2100
(110)
2500
P
i
f
kVA
Hz
n