PLA34 power quality analyser cl. S

Power quality analysers is designed according to the norm IEC 61000-4-30 cl. S ed. 3 for continuous measurement of electrical parameters in LV and MV systems for further power quality investigation. The PLA34 is built with a powerful RISC processor that provides sufficient processing capabilities for real-time measurement and calculation of all parameters and values.

sampling frequency 40 kHz
U and I accuracy 0.2
communication interfaces Ethernet, USB, RS485
communication protocols Modbus RTU, Modbus TCP, SNTP, SMTP, FTP, HTTP, MTP, MQTT
RS485 Modbus gateway
2 x digital I/O
3 voltage and 4 current inputs

measuring according IEC 61000-4-30 ed.3 cl. S
harmonics, inter-harmonics EN 61000-4-7 up to 64th
flicker measurement according EN 61000-4-15
suitable for PQ reports EN 50160
transient detection > 25 μs
events detection > 10 ms
avg, max, min recorded value
EN50160, PGC PQ logging

on board logging Flash memory 1GB
WWW-server and email notification
DIN rail mounting design
PMS SW for configuration, monitoring and evaluation
universal auxiliary supply voltage
MQTT support
PQDIF export

Function

Voltage and current signals are digitalized by high class A/D converter and computing with RISC microprocessor. Effective values are computed continuously in 200 ms (10 periods) windows. Independently on this computing is for events detection each 10ms counted efective value of U and I. Another absolutely independent part is transient detection that are directly detected from samples of digitalized U and I.

IEC 61000-4-30 ed.3 cl. S

PQ analyzer PLA34 measures according the standard IEC 61000-4-30 ed. 3 class S. Such type of analyzers are used in applications where there is necessary precise measurement for power quality evaluation according norms EN 50160, EN 61000-4-7 and EN 61000-4-15.

Events

Events are unexpected signal changes with duration from 10ms up to days. In some installations these events can cause material damages and economical lost. Norm EN 50160 defines limits of events and its quantity that can appear in electrical grid during a year. PQA PLA34 evaluates following type of events DIP, INT, SWELL, RVC and I_MAX.

Transients

Transients are very short events with duration of us, that can cause instruments failure or even their damage. For detection of transients are used samples of signal that depends on sampling frequency of PQA. As high sampling as shorter transients can be detected. Power quality analyser PLA34 use sampling rate 40 kHz that allows to detect transients longer that 25 μs.

Webserver

Device has embedded web server for remote monitoring of the PLA34 instrument over the Internet.

Software

Software PMS - Power Monitor System offers possibility for essential configuration of PLA34. More over it is a tool to define recording template, alarms, and defined events and transients limits for PQ evaluation. Another part of PMS SW is used for PQ evaluation and report generation.

MQTT

integration of this protocol into PLA34 allows implementation of instrument into any SW. Measured data are divided into several topics in which user can chose which one want to receive. Measured data are transferred in file format JSON.

Measured parameters

Parameter	Range	Display	Accuracy
phase voltage	10...600 V	1 V...1 MV	0.2%
line-line voltage	18...1000 V	0...1 MV	0.2%
system frequency	40..70 Hz	40...70 Hz	10 mHz
current	0.001...8.5 A	1 mA...1 MA	0.2%
cosΦ	0.01L...0.01C	0.01L...0.01C	1%
power factor	0.01L...0.01C	0.01L...0.01C	1%
THDU L-N	0...999%	0...999%	5%
THDU L-L	0...999%	0...999%	5%
THDI	0...999%	0...999%	5%
U harmonics	0...999%	0...999%	class 1
group of U interharmonics	0...999%	0...999%	class 1
group of U harmonics	0...999%	0...999%	class 1
P harmonics	0...999%	0...999%	class 1
Q harmonics	0...999%	0...999%	class 1
I harmonics	0...999%	0...999%	class 1
group of I interharmonics	0...999%	0...999%	class 1
group of I harmonics	0...999%	0...999%	class 1
short-term flicker	0.4...10.0	0.4...10.0	class A
long-term flicker	0.4...10.0	0.4...10.0	class A
under-voltage	0...100%	0...100%	0.4%
over-voltage	0...100%	0...100%	0.4%
asymmetry of voltage	0...100%	0...100%	0.3%
N wire voltage	10...600 V	0...1 MV	0.2%
K-factor
asymmetry of current			0.5%
PQ transients			25 μs
PQ events			10 ms
ripple control
active power	0...15.3 kW	0...9999 GW	0.4%
reactive power	0...15.3 kvar	0...9999 Gvar	0.4%
apparent power	0...15.3 kVA	0...9999 GVA	0.4%
distortion power			0.5%
active energy +/-	0...9999 GWh	0...9999 GWh	class 1
reactive L energy +/-	0...9999 Gvarh	0...9999 Gvarh	class 2
reactive C energy +/-	0...9999 Gvarh	0...9999 Gvarh	class 2

Technical features

Parameter	Value
auxiliary supply voltage	85 ... 250 VAC/DC (±10%) or 24 ... 60 VAC/DC (±10%)
self consumption	< 5 VA
time uncertinity	< 1 s a day
number of I/O	2
VT and CT ratio	1...750 000
sampling rate	40 kHz
event detection	> 10 ms
transient detection	> 25 μs
logger memory	1 GB flash
display	LCD
communication interfaces	RS485 / LAN / USB
communication protocols	Modbus RTU, Modbus TCP, SNTP, SMTP, HTTP, FTP, MTP, MQTT
ambient temperature	-25°C...+70°C
dimensions	96 x 96 x 60 mm
weight	300 g
protection degree	IP20 rear side / IP54 front panel
related standards	EN 61000-4-30 class A / EN 61000-4-7 / EN 61000-4-15 class A / EN 61557-12