Specifications

Siemens Mobility, Traffic Solutions
Sopers Lane, Poole, Dorset
BH17 7ER
Version 10 Page 118 of 120 Status Issued
Last Editor harry.smyth Date 03 November 2014
Document
Name
GENERAL HANDBOOK FOR HEIMDALL
DETECTORS
Doc. No. 667/HB/31900/000
Copyright  Siemens plc 2014 All Rights Reserved
The calculations may be worked out using the tabular form shown below:
Cable
1
Cable
2
Cable
4
Cable
3
Current
+ + + =
Total
Current
x Rs =
Volts
=
Volts
- 19. 2 =
Amps
=
(Transformer
voltage drop)
(Maximum allowable
Voltage drop in any cable)
(Lowest transformer
voltage)
Maximum allowable
cable length =
Voltage drop
in Cable 1
Metres
(Cable 1)
X 0.042 =
(or 0.021 for
conductors in
parallel
Vs (min) -
Table 12-3 - Calculation of Maximum Cable Length (Controller-mounted AC supply)
Note: The above chart yields the maximum length of one cable. The calculation within
the dashed area must be repeated for the other cables.