R.T.A. s.r.l. – ADW_ME05 – 09/21
18/22
7.2- Transformer must meet the following requirements:
- Supply the correct voltage through a transformer secondary winding. The V
AC
voltage value is
intended as measured at secondary terminals in no load condition and with primary voltage equal to
the nominal value. Maximum voltage drop at full power load must be less than 5%.
- Ensure the galvanic insulation between the drive circuits and the main.
Remember that direct
connection of drive circuits to the main is strictly forbidden. The use of autotransformer is
strictly forbidden.
- Ensure the galvanic insulation between the drive circuits and all other circuits of the same machine.
This means that the drive dedicated transformer secondary has to be used exclusively for the
drive.
7.3- The use of one secondary winding for more drives (max 3 drives) is allowed only if the total power
required by the drives is less than 600VA.
7.4-
Branch circuit protection fuses F1 and F2 (see Fig. 7a and Fig. 7b) must be time delay of 10
Amp, at least 250 Volt with I
2
t between 150 A
2
s and 400 A
2
s (for example Littelfuse 215010.P).
7.5-
Fuse F3 (see Fig.7a and Fig. 7b) must be uf type KTK-R-8 by COOPER BUSSMAN LCC or
equivalent [Branch circuit protection fuses].
Fuse F3 is mandatory for UL compliance.
7.6- The cross-section area of conductors used in power supply circuit must be chosen according with
power dimensioning (see 7.1). The cross-section area of the four shielded conductors connecting
motor to the drive must be chosen with regard to the nominal current which has been set in the drive.
IMPORTANT NOTES
1) C
≥
10.000 µF with
V
DC
= 24 Volt
C
≥
4.700 µF with
V
DC
= 75 Volt
2) Transformer power: from
100 to 300 VA depending on:
•
Drive model
•
Current setting
•
Motor model
•
Motor speed
•
duty-cycle
3) Rectifier bridge type:
according transformer
power.
4) C capacitor must be near
AM2 or C1 connector; max
cables length = 1 meter.
5) The maximum motor cable
length is 20 meters; Section
according to phase current
RMS value.
Fig. 7a - Drive external connection scheme for ADW 04, ADW 04.V,
ADW 06 and ADW 06.V drives.