7.
Danger of fatal injury from electric shock!
➤ Switch off and lock out the supply disconnecting device and check that no voltage is
present.
8. If necessary: Set up the machine for the correct power supply voltage as described in chap‐
9. Connect the power supply.
Further information The electrical diagram 13.4 contains further specifications for electrical connection.
6.5.1 Changing main voltage connections
Machine set up for [V]
208
230
460
Machine may be modified
[V]
230
208
208
460
460
230
Tab. 26 Voltage selection
The following parts have to be considered for making the change:
■ Motor connection terminals in the control cabinet
■ Drive motor overload protection relay
■ Control transformer
■ Transformer for the refrigerated dryer (only if present).
Material The required jumpers (also known as ’bridges’ or ’links’) are provided in the control cabinet.
Precondition A check has been made to ensure no voltage is present.
Changing the drive motor connection
➤ Open the control cabinet and connect the motor in accordance with the electrical diagram.
Adjusting the overload protection cutout
➤ Check the overload protection relay setting.
SM 7.5
SM 10
SM 15
208V, 3-ph, 60Hz [A]
15
20
25
230V, 3-ph, 60Hz [A]
14
19
24
460V, 3-ph, 60Hz [A]
7
10
12
Tab. 27 Overload protection cutout settings.
Connecting the control transformer
The pimary winding of the control transformer is not connected. The machine will not run without
connecting the control transformer according to the power supply.
➤ Open the control cabinet and connect the control transformer in accordance with the electrical
diagram.
6
Installation
6.5
Making the Power Supply Connection
38
Operator Manual Screw Compressor
SM Tri-Voltage, SIGMA CONTROL 2
9_5875 33 USE
