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SALICRU
4.3.7. Terminals for EPO.
The UPS has two terminals to install an external button of emer-
gency output shutdown (EPO).
4.3.8. Control panel.
The UPS from
SLC CUBE3+
series has a sophisticated control
panel managed by a microntroller, which acts as a interface mode
between the UPS and the end-user.
Depending on the model, it is equipped with an alphanumerical
panel or touchscreen. Automatically, both devices informs to the
end-user about the current status of the equipment and the elec-
trical measurements by means of a tree menu, allowing an easy
browsing through their screens.
4.3.9. Control software and communications.
AFC Control (Adaptive Feedforward Cancellation).
It consists in the use of digital resonators connected in parallel and
set to those frequencies where the consigns or perturbations to
refuse are expected.
This control technique allows doing the follow of the sinewave sig-
nals of reference of the output voltage in the inverter and input cur-
rent of the active rectifier.
It is important to highlight that the different controls of the UPS
do not operate either isolated or locally, but they interact between
them in such way that it results a global controller of coupled type.
It means operating advantages like to adapt the rectifier to the load
conditions immediately.
The digital control software works at two different levels:
4.3.9.1. Control software at low level.
•
Input three phase rectifier controller
: PFC control and bat-
tery charge loops. The structure adopted of independent control
per phase of cascade type allows managing both single phase
and three phase inputs.
The AFC control technique has been also applied, to assure a
sinewave mains currents, with a THDi < 2%, and in phase
shifting with the voltages, to balance the active power of all
the system, to accelerate its response and make it insensitive
against the load transients.
In normal conditions, the rectifier is running and charging the
batteries, controlling at any moment the charging current and
floating voltage according to the temperature of themselves.
The system is also in charge of minimising the charging current
ripple that flows through them.
When the input voltage or frequency is out of the correct op-
erating range, it is shutdown and batteries are responsible of
keeping the inverter in operation, which at the same time sup-
plies the loads connected at the output of the equipment till the
battery voltage decreases till the end of back up time.
Another important feature of the rectifier is its bidirectional ca-
pacity of operation. This allow consigning a battery discharging
current even with mains present. This quality performance will
make possible to do a battery test both in full load and no load
conditions.
•
Output three phase rectifier controller:
independent per
phase, it is easy adapted to different settings, either single
phase or three phase.
It is highlighted the use of the AFC control technique that al-
lows getting an output voltage with a THDv lower than 1,5%
with non-linear load at the output and good dynamic response
against unexpected step loads.
•
Switching algorithm of the bypass thyristors
.
•
Parallel control
: high speed communication and inverter par-
allel connection.
4.3.9.2. Managing software of the equipment.
•
Managing and control of different parts.
•
Visualisation software for user interface.
•
Software of communication and protocol implementation.
•
Managing software of parallel system.
4.3.9.3. Communications.
•
COM port to relays
: It supplies a digital signals in a dry con-
tact way, which makes possible the dialogue between the
equipment and other machines or devices.
By default the equipment is supplied with 4 signal relays with
a preset programming (see chart 3), which can be modified at
factory or by the
T.S.S.
under request. Chart 7 shows all the
alarms that can be set to any relay. A fifth relay can be supplied
as an option and under request, which can be defined in the
purchase order.
Also there is a “shutdown” input that allows shutdown the in-
verter.
The most common use of this type of port is to supply the
needed information to the closing file software.
•
USB port
: The equipments includes a connection by means
of Type-B connector, USB port, performing as a virtual serial
port («Virtual COM Port», or «VCP»). When connecting the PC to
such port, the «VCP» «driver» will be automatically installed, so
the USB port will perform as a COM 0 serial port of the equip-
ment.
The connection of a PC to the USB port of the UPS, disables
the operation of the COM 0 port through the RS232/RS485 too.
So, it means, that the USB communication has priority over the
RS232/RS485.
The standard protocol for this port is Modbus, the same one as
for the RS232/RS485.
•
COM port RS232/RS485
: By means of the same DB9 con-
nector supplies the RS232/RS485 communication ports. They
are mutually exclusive between them and they are used to con-
nect the UPS with any machine or device that has this standard
bus.
The
RS232
port consists in the serial transmission of data, in
such way that it can send a lot of information through a com-
munication cable of 3 wires.
The
RS485
, unlike other serial communication channels, it uses
2 wires only to dialogue among the systems connected to this
network. The communication is established by sending and re-
ceiving signals in differential mode, so it gives to the system
