Thytronic SME2-IS User Manual

32
32
SME2-IS - Manual - 06 - 2021
FUNCTIONAL CHARACTERISTICS
— Voltage present - RVL
Foreword
This function reports whether voltage is available or not.
The signal (TSV) is supplied to the remote control unit via the closing of a contact connected to ter-
minal 3 of the MB terminal block and to the communications interfaces.
Measurement criterion
The voltage absent/present protection employs the fundamental component of the three phase volt-
ages U
L1
, U
L2
, U
L3
.
Operating logic
and regulations
Each of the three measured voltages is compared with the set thresholds.
The start and trip logic of the voltage absent protection function is "AND", so that the threshold starts
when all three measured voltages fall below the congurable threshold.
The start and trip logic of the voltage present function is "OR", so that the threshold starts when at
least one of the three measured voltages returns above the congurable threshold.
The voltage present/absent signalling function has two adjustable thresholds with the following de-
fault settings:
• Trip: 80% nominal voltage,
• Restore: 20% nominal voltage.
The thresholds determine the passage between voltage present/absent as follows:
- starting from no voltage on the line, the Voltage Present logical status is recognised when the fol-
lowing condition holds for at least 250 ms:
(V4>80%Vn) OR (V8>80%Vn) OR (V12>80%Vn)
- from from Voltage Present On, the logical status is no longer recognised when the following con-
dition holds:
(V4<20%Vn) AND (V8<20%Vn) AND (V12<20%Vn) after 500 ms.
If the 24VDC power fails and is restored, the logic starts from the status Voltage Absent, and only
when the condition
(V4>80%Vn) OR (V8>80%Vn) OR (V12>80%Vn) is restored does it recognise Voltage Present.
The following gure illustrates the logic for the voltage present/absent function.
— Overcurrent - 50/51
Foreword
Operating logic for the voltage present/absent function
0.2 Un
0.8 Un
Status of the voltage
present/absent function
Voltage V4 - V8 V12
t
V4, V8,V12
0.25s 0.5s
voltage presentvoltage absent voltage absent
(LED+RELAYS)
U<TR-L
27-59 LOGIC
Trip U<
U
L1
U
L2
U
L3
Functional diagram for the threshodl of the voltage present/absent function
0
T
≥
&
State
U ≥ U>
def
U>
def
0.250 s
&
U
L1
U
L2
U
L3
&
State
U ≤ U<
def
U<
def
0
T
0.500 s
OPERATION DESCRIPTION

Thytronic SME2-IS Specifications

General

Brand	Thytronic
Model	SME2-IS
Category	Security Sensors
Language	English