Simex SRT-457, User Manual

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User manual - METER SRT-457
SEtP - first threshold of the relay (range -999 ÷ 9999). Negative values can be input by
selecting a “-” sign on first digit (to change value use
[^] and [v] buttons).
Threshold is the medium value of relay hysteresis.
SEt2
- second threshold of the relay (range -999 ÷ 9999). Negative values can be input
by selecting a “-” sign on first digit ( to change value use
[^]
and
[v]
buttons). This
threshold is accessible when
modE
parameter is set to
in
or
out
value.
Threshold is the medium value of relay hysteresis.
HYSt - hysteresis of relay (range 0 ÷ 999). Full hysteresis of the relay is equal to 2x
HYSt
parameter. The relay state can change when an input signal is out of
threshold-hysteresis
to
thhysteresis
zone.
Presented parameters should be set to ensure that
SEtP + HYSt ,
SEt2 + HYSt , SEtP - HYSt or SEt2 - HYSt do not exceeds the
measure range. Additionally, in two threshold mode (“ modE ”= „ in ” or „ out ”), the
hysteresis for both thresholds must not cover each other (in other case relay can't
change his state).
modE - relay operation mode:
noAC - the relay is not active (permanent turned off)
on
- one threshold mode, the relay is turned
ON
when input signal exceeds
SEtP + HYSt value , and is turned off back when the input signal became
lower than SEtP HYSt ,
oFF - one threshold mode, the relay is turned OFF when input signal exceeds
SEtP
+
HYSt
value
,
and is turned on back when the input signal became
lower than
SEtP HYSt
,
in - two threshold mode, the relay is turned ON when the input signal is
bigger than “ lower threshold + HYSt ” and lower than “ bigger
threshold – HYSt ”, and turned off when the input signal is contained in
the second zone. The bigger threshold means bigger one of
SEtP
and
SEt2
thresholds, the
lower threshold
” means lower one of
SEtP and SEt2 thresholds.
out - two threshold mode, relay is turned ON when the input value is bigger
than “ bigger threshold + HYSt and lower than “ lower threshold –
HYSt , and turned on when the input signal is contained in the second
zone. The bigger threshold means bigger one of
SEtP
and
SEt2
thresholds, the
lower threshold
” means lower one of
SEtP
and
SEt2 thresholds.
modb
- the relay is controlled via RS-485 interface, independently on the input
signal.
• LEDs light when relays are closed , independently of relays' mode.
• When power supply fail, unit do not store relays state selected by RS-485
interface.
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