User manual - RATEMETER STI-73
6.3.2.
Two thresholds mode
Description:
A, B, C, D, E
- points where measured signal exceeds border values (expected value ± allowed deviation)
B
ON
,
B
OFF
,
C
ON
,
C
OFF
,
E
ON
,
E
OFF
- relays state changes moments: (for
“t on”
> 0,
“t oFF”
> 0)
t
A
,
t
B
,
t
C
,
t
D
,
t
E
-
time periods while input signal is in zone A or zone B
Figure 6.5. Principle of LED/relay output operation for two thresholds mode
Figure 6.5 presents the principle of relay outputs operation for two thresholds mode, and an
example values of other parameters. In this mode parameter
“SEt P2”
is accessible in
common with
“SEt P2”
, this parameter describes a second threshold of the relay output. The
parameters
“HYSt”
,
“modE”
,
“t on”
,
“t oFF”
,
“unit”
and
“ALArmS”
are connected with both
“SEt P”
and
“SEt P2”
thresholds. While the controlling process, the relay output changes his
state depends of both
“SEt P”
and
“SEt P2”
thresholds in similar way as it was described in
one threshold mode.
If two threshold mode is used,
“modE”
parameter defines state of the relay output when
the input value occurs in a particular zone defined by
border values
of both
thresholds
. The
relay can be turned on if the input value is contained in
zone A
(
“modE”
=
”in”
) or
zone B
(
“modE”
=
”out”
) and turned off if it is contained in the second one
(Figure 6.5).
19
E
OFF
“SEt P”
or
“SEt P2”
parameter
“HYSt”
parameter
measure
d signal
displayed value
time
time
time
A
B
C
D
relay state
(
modE
=
in
t on
= 0
t oFF
= 0)
relay state
(
modE
=
in
t on
> 0
t oFF
> 0)
t
A
t
C
t
D
B
ON
relay state
(
modE
=
out
t on
= 0
t oFF
= 0)
relay state
(
modE
=
out
t on
> 0
t oFF
> 0)
“t oFF”
parameter
“t on”
parameter
B
OFF
E
ON
time
time
closed
open
a)
b)
c)
d)
e)
open
closed
open
open
closed
closed
“t on”
parameter
“t oFF”
parameter
zone A
zone B
“HYSt”
parameter
zone B
C
OFF
C
ON
E
“t on”
parameter
“t oFF”
parameter
t
B
t
E
