Salicru SLC ADAPT2 Series User Manual page 19

Smart parallel logic provides maximum flexibility to the
user. For example, stopping the inverter (switching to by-
pass mode) or starting it up (transfer to inverter mode) can
be done from any UPS in a parallel system. In both parallel
systems and in a single UPS, transfers from Normal to By-
pass modes and vice versa are synchronised. For example,
when an overload is detected in a UPS, it is automatically
transferred to Bypass. If the overload disappears, the
parallel system automatically recovers normal operation,
transferring the load from Bypass to the Inverter.
4.3.2.2.2. Features of the parallel system.
The performance of an SLC ADAPT2 parallel system is similar
to a large UPS with the advantage of greater reliability and
adaptability. For a system to operate correctly with the load,
the following requirements must be met:
1.
All of the UPSs must be identical, even though they do not
contain the same number of modules.
2.
All of the UPSs must be powered by the same AC line.
3.
In case of devices with an independent bypass line, the
power supply network will be the same for all of them.
4.
Both feeds, points 2 and 3, must be referenced to the same
neutral potential.
Isolation transformers are optionally available for
installations where the sources do not share the
same neutral reference or where it is not available.
4.3.2.3. Sleep operating mode.
Usually the dimensioning of a modular UPS is based on
•
the power required for the loads, plus the redundant mod-
ules estimated with the expression N+n; where "N" is the
number of modules permanently in parallel in order to ob-
tain the required rated power and "n" is the number of re-
dundant modules. Beyond this planned over-dimensioning,
all the modules operate by load sharing, delivering the
same unit power to obtain the total amount required, which
implies a lower performance than desired. In order to solve
this problem and increase the efficiency of the system, one
of the two sleep modes can be activated at the factory or
subsequently by the T.S.S.:
"Smart Sleep". This advanced technology applied to
ˆ
the ADAPT2 UPS series allows you to seek the maximum
performance point even when working with low loads.
This is achieved by activating one of two possible modes,
although each has a different purpose:
Normal Sleep mode. The inverter of the modules
–
is activated but in standby, with its output discon-
nected from the load. In this way, the "sleeping"
modules can be connected to the load in seconds,
with no transfer time at all if the Bypass can supply
the load during this time.
Deep Sleep mode. All the power converters of the
–
modules are completely off with their outputs dis-
connected from the load. Activation takes several
minutes, with no transfer time at all if the Bypass
can supply the load during this time.
USER MANUAL
"Cycling". In addition, the cycling function is available,
ˆ
to allow all of the modules to age at the same rate, by
alternating which are active and which are idle. The
minimum programmable cycling period is three months.
Distribution of the load in normal operation.
Distribution of loads and cycling of the UPSs.
Fig. 12. Graphic example of normal operation or cycling.
4.3.3. Operating statuses.
The modular system described is part of the on-line double-con-
version UPS family, with static bypass line and manual mainte-
nance bypass (optional). The available operating statuses are:
Normal status.
•
Battery status.
•
Bypass status.
•
Manual Bypass status (optional).
•
Status - ECO mode.
•
Status - Frequency converter (CF) mode.
•
In the description of the operating statuses, the operation de-
scription refers to the PFC-rectifier and inverter parts as func-
tional parts of one module, although there will be as many of
them as there are modules connected in parallel.
In the following diagrams, when the manual bypass
switch is mentioned, it must be remembered that this,
when it exists, will always be external or optional.
4.3.3.1. Normal status.
The inverters of the power modules installed in the UPS feed
the critical load. The PFC-rectifier, which is supplied by the AC
mains, simultaneously supplies direct current to the inverter
and the battery charger, which maintains them in an optimal
state of charge.
Manual bypass
AC input
Static bypass
Bypass
 
PFC rectifier
AC / DC
AC input
BAT / DC
Rectifier

DC / DC Battery

Charger
Batteries
Fig. 13. Flowchart in Normal status.

Inverter
AC output
DC / AC
Connection strips between
phases for mains.
SLC ADAPT 2 - UNINTERRUPTIBLE POWER SUPPLY SYSTEM -
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