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9 REMOTE REFERENCE UNIT
As detailed in section 3, the determination of the measured phase requires communications
with a Remote Reference Unit. The unit can provide immediate phase indication if the
communications with the Remote Reference Unit is available, or at a later time, when the stored
data is post-processed with the Remote Reference Unit data.
NOTE
: The Remote Reference Unit is not installed into the local substation. The Remote
Reference Unit only needs to be installed at a point where the Supply Network is synchronised.
For example, the supply network across the United Kingdom is synchronised and therefore the
Remote Reference Unit can be installed at any location anywhere in the United Kingdom. There
is already a Remote Reference Unit installed at the HAYSYS Offices in Cardiff and all UK based
PIUs can communicate with this Remote Reference Unit.
The Remote Reference Unit is for indoor use only.
If required, a Remote Reference Unit can be supplied and installed within the customer’s own
premises. The Remote Reference Unit looks the same as a PIU but simply has a different mains
charger socket (a 2.5mm socket instead of a 2.1mm socket) and different firmware installed.
The reference unit does not use the E-Field Probe to measure the local phase, but the connected
A.C. mains charger instead.
REMOTE REFERENCE UNIT
(CHARGING COVER REMOVED)
INTERNET CONNECTED PC
MAINS CHARGER
SATELLITE
COMMUNICATIONS
Figure 18 – Remote Reference Unit Configuration
The Remote Reference Unit is connected via USB to the Internet Connected PC (not supplied),
that runs a Bridge application (supplied). The PC must be connected using a public static IP
address. The Bridge application is a Windows based application that provides a data link
between Remote Reference Unit and PIU units.
The Remote Reference Unit measures the instantaneous phase of the mains connected charger
and not the E-field sensor (no E-Field sensor is required).