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charged, the normal condition, the AMPS should nominally be close to 0. CHARGE indicates an
estimate of the amount of charge left in the batteries. Nominally this value will be 100% indicating the
batteries are fully charged. If the utility fails and energy must be drawn from the batteries, this value will
start to drop. If it reaches less than 2%, the batteries are considered to be drained of their usable
energy, and the UPS output will shut down to protect the batteries from being damaged due to a deep
discharge.
The very bottom line of this display is a status line. Normally it will be blank; however, if the UPS has
detected an abnormal condition, this line will flash the cause of the abnormality.
5.3.2 DISPLAY #2 Screen
This screen shows additional real-time UPS parameters that could not be included on DISPLAY #1. An
example of this screen is shown below:
The first line and last line are identical to those described in DISPLAY #1. The first column of the
screen contains temperatures of the 3 heat sinks, the inside ambient, and the room in centigrade. The
heat sink and ambient sensors are used for thermal protection -- if these temperatures get too high, the
system will first issue a WARNING alarm. If the temperature continues to increase, the system will shut
down to protect itself from damage. Shutdowns of this nature are referred to as Temperature
Overloads. The temperatures will normally stay well below these warning and shutdown thresholds,
unless there is a problem with the cooling fans.
The middle column of this display contains kilo-volt-amperes and kilowatts drawn from the AC line and
supplied to the load, and kilowatts drawn from the batteries.
The upper half of the last column of this display contains battery current data. Internal Battery Amps is
a measure of the current drawn from the internal batteries. External Battery Amps is a measure of
current drawn from external batteries, should your system have an external battery cabinet. If your
system has external batteries, the UPS is configured to control them through the SET PARAMETERS
function. If you disconnect the external batteries, or if the external battery breakers are turned off, or if
your internal or external batteries are bad, the UPS uses these two currents to detect such problems. It
then uses this information to modify its battery charging current and notify the operator of the problem
via a WARNING alarm.
The bottom half of the last column of this display contains the current flowing in the output Neutral wire
to the load. With a perfectly balanced 3-phase linear load, this current should ideally be 0. However,
unbalanced loads and/or highly nonlinear loads may result in a large Neutral current. If left unchecked,
such a high Neutral current could result in the overheating of the wire carrying the Neutral current. This
parameter is monitored by the controls for such a condition. If this Neutral current exceeds 125% of the
rated current for your UPS, an overload condition will occur and the UPS will shut down after
approximately one minute.
0 1 / 1 1 / 9 9 M E S T A E L E C T R O N I C S 1 6 : 5 2 : 1 1
T E M P E R A T U R E S
| _ _
K V A / P O W E R
_ _ |
B A T T E R Y A M P S
H S I N K A =
2 7 C | _
I N _ K V A =
0 . 9 |
I N T _ =
0 . 3
H S I N K B =
2 9 C |
O U T _ K V A =
0 . 0 | _
E X T
_
=
0 . 6
H S I N K C =
2 8 C | _ _
I N _ K W =
0 . 5 |
N E U T R A L O U T
_
A M B =
2 7 C | _
O U T _ K W =
0 . 0 | _
A M P S =
0
R O O M =
2 3 C |
B A T T _ K W =
0 . 1 |
% R A T E D =
0 %
