Filter
Top Products
MDS-D/DH Series Specifications Manual
6-4 Branch-circuit protection (for control power supply)
6 - 11
6-4 Branch-circuit protection (for control power supply)
6-4-1 Circuit protector
This breaker is used to switch the control power and to provide overload and short-circuit protection.
When connecting a circuit protector to the power input (TE3 terminals L11 and L21) for the control circuit, use a
product that does not trip (incorrectly activate) by a rush current when the power is turned ON. A circuit protector
with inertial delay is available to prevent unnecessary tripping. Select the product to be used according to the
machine specifications.
The rush current and rush conductivity time differ according to the power impedance and power ON timing, so
select a product that does not trip even under the conditions listed in the following table.
6-4-2 Fuse protection
The fuse of branch-circuit protection must use UL class CC, J or T. In the selection, please consider rush current
and rush conductive time.
Selection of branch-circuit protection fuse
When collectively protecting the control circuit power for multiple units, select a circuit protector that
satisfies the total sum of the rush current Ip.
The largest value is used for the rush conductivity time T.
Connected total of unit
Fuse (Class CC) Wire Size
Rated [V] Current [A] AWG
1 - 4
600
20
16 to 14
5 - 8 35
For continued protection against risk of fire, replace only with same type 600 V, 20 or 35 A
(UL CLASS CC) fuse.
Before replacing fuse, confirm all power controlling the drive system is shut-OFF. Be sure to look out
the power source to prevent the power from being turned ON while maintenance is being performed.
t [ms]
Time
constant:
MDS-D series: T = 9ms
MDS-DH series: T = 18ms
Note) Rush current of MDS-D-37/75 is 38A.
I [A]
Rush conductivity time:
Time to reach 36.8% of rush current Ip,
equivalent to circuit protector operation characteristics
operation time.
Rush current
MDS-D series: Ip=30A
MDS-DH series: Ip=18A
(per 1 unit)
36.8%
POINT
CAUTION
WARNING