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ST750
G
ENERAL
H
ANDBOOK
667/HB/33750/000
Page 26
Issue 6
Note
:
The controller power should also include any additional equipment
supplied by the controller. This may include, for example, OTU, OMU or
Auxiliary detector power supply.
For the total average junction power to aid with running cost estimates, the total
average lamp power must be added to the total average controller power.
Total average junction power is calculated as follows:
Total average lamp power
916 W
Total average controller power
46 W
Total average junction power
962 W
If an estimate of running costs is required that includes the period of time that the
signals are dimmed, this can be approximated as follows:
Total average Junction Power (Dimmed) is:
Total average Signal Power x (Dimmed Voltage / Nominal Mains voltage)
plus Total average Controller Power.
Therefore for the theoretical crossing in Figure 1:
Total average Junction Power (Dimmed)
= (916W x (160V/240V)) + 46W
=
657 W
2.4.5 Connection to Un-Metered Supplies (UMS)
If the ST750 is to be connected to an unmetered supply (UMS) equipment codes for
the agreed power consumption of the controller and all associated equipment may
be found on the Elexon web site.
General information may be found at:
http://www.elexon.co.uk/participating/unmeteredSupplies.aspx
The actual charge codes may be found by following the link below, which is correct
at the time of writing:
Note that a condition of using these codes is the creation of a full site inventory to
create a costing for the supply of electricity. Details on this process may be found
by following the link below, which is correct at the time of writing: