Direct-to-mains power source (non-isolated) – ElmoMC Gold Line Digital Servo Drives-Gold Tuba User Manual
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Gold Tuba Installation Guide
MAN-G-TUBIG-EC (Ver. 1.201)
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The AC power for the Gold Tuba can be delivered from either directly from the mains or from a
single or three-phase isolated transformer. The following sections contain topology
recommendations for implementing three-phase and a single-phase supply chains.
The power stage of the Gold Tuba is fully isolated from the other sections of the Gold Tuba, such as
the control-stage and the heat sink. This isolation allows the user to connect the common of the
control section to the PE, a connection which significantly contributes to proper functionality,
safety and EMI immunity, leading to better performance of the Gold Tuba.
This isolation allows the Gold Tuba to operate with a non-isolated source (a direct-to-mains
connection) which eliminates the need for a bulky and expensive isolation transformer.
As well as operating from a non-isolated/direct-to-mains AC supply, the Gold Tuba can also operate
from an isolated transformer.
The AC voltage level must be limited to 270 VAC so as not to exceed the maximum supply voltage in
the case of a 230 VAC drive, or 528 VAC so as not to exceed the maximum supply voltage in the case
of a 480 VAC drive.
7.3.1.
Direct-to-Mains Power Source (Non-Isolated)
This section relates to the configuration of the drive, which is connected directly to the mains.
To connect the non-isolated AC power supply:
1.
For best noise immunity, a shielded (not twisted) cable is recommended (not mandatory) for
the AC input cable.
2.
A 4-wire shielded cable should be used:
a.
Connect the 3-phase leads of the main input cable to the AC1, AC2 and AC3 terminals of the
main input connector.
b.
For safety requirements, the green/yellow-wire must be connected to the protective earth
(PE terminal). Connect the Protective Earth wire to the PE terminal on the main AC
connector.
c.
For better EMI performance, the shield should be connected to Protective Earth (PE).
3.
The gauge of the cable strands is determined by the actual current of the drive.
Caution For all the following Topologies:
•
Do not connect VN- to PE. In a direct-to-mains connection the VN- must not be
connected to the PE, as this will cause irreparable damage to the system.
•
Take care and note that in a direct-to-mains connection the Neutral point is not
the most negative voltage level. It is the mid-point level of the rectified DC bus.