Specifications

Main variables
Variables that can be monitored and displayed
System
Average
(dmd)
Min
RS485/232
Optical
Analogue Out
V
LL
,V
LN
V asymmetry
A
An
Hz
VA
var
W
PF
+kWh (*)
-kWh (*)
+kvarh (*)
-kvarh (*)
THD (A-V)
THD even (A-V)
THD odd (A-V)
Single harmonic
Single ph Max Alarm Out Pulse
(*) Total and time-period energies
Analysis of the power quality and control of the electrical parameters
The problems that more frequently occur in electrical
systems with inverters and power converters, switching
power supplies for computer and communication system
applications are the following:
• failures on compensation capacitors;
• blowing of capacitor fuses;
• overheating of power supply transformers with a load
current below the rated value;
• overheating of motors and frequent failures;
• high neutral conductor currents;
• problems on electronic motor controls.
They are mainly due to the harmonic contents of currents
and voltages.
The best solution is WM5 96 or PQT H that allows to
continuously monitor the harmonic contents (up to the
63rd harmonics) of currents and voltages together with all
other electrical parameters.
The control of up to 16 different electrical parameters by
means of alarm set-points with a specific logic (OR/AND)
and the automatic recording of up to 10 000 events (alarm,
min, max, digital input status, reset) allow the operator to
monitor any anomaly of the installation and of the loads in
real time, so as to promptly decide and plan any
maintenance actions, thus avoiding possible damages to
the loads and/or expensive stopping of the machinery.
35
Easy and fast communication
A front optical communication port based on ANSI C12.18
and Modbus protocols can be used to carry out an easy and
fast communication with a PC or laptop. The proper Wm5Soft
(for WM5 96) or PqtHSoft (for PQT H) software allows the
user, through a multi level login procedure to:
• Read the measurement data and show them as a matrix on
the monitor;
• Program all the parameters to quickly and easily adapt the
instrument to the application needs;
• Download the stored events (alarm, min, max, digital input
status, reset) in a XLS format to easily build up an
installation history;
• Recalibrate the instrument, when needed, directly from a
local support;
• Upgrade the instrument firmware improving its
characteristics and therefore adding more and more value.