Siemens ST950 - Page 28

Mobility, Intelligent Traffic Systems
Sopers Lane, Poole, Dorset, BH17 7ER
Security classification
Unrestricted
Page
28 of 154
Version
7
Status
Issued
Last Editor
manpreet.jeerh
Date
January 2020
Document Name
ST950 ICM Handbook
Document No.
667/HE/45950/000
Copyright © Siemens plc 2020. All Rights Reserved. Mobility is a division of Siemens Plc
Figure 10 – ELV Transformer Connections: 120V mains
Figure 11 – ELV Transformer Connections: 110V mains
The LPU Mains Live wire is always connected to the extra 230V
termination on the ELV transformer.
When operating on 110V or 120V Mains input, the LPU Mains Live wire remains
connected to the extra 230V termination. This results in the LPU being supplied with
110V AC.
110
Earth
Earth
250
Earth
Earth
Live Input
Live to LPU
Neutral Input
220
230
Neutral to LPU
120
0
240
120
230
Earth
Earth
250
Earth
Earth
Live Input
Live to LPU
Neutral Input
220
230
Neutral to LPU
120
0
240
120
230
110