PDU–4xx–W
©
Dinel, s.r.o.
30
Two thresholds mode
Fig. 20 presents the principle of relay outputs operation for two thresholds mode, and an example
values of other parameters. In this mode parameter
“SEt2”
is accessible in common with
“SEtP”
,
this parameter describes a second threshold of the relay output. The parameters
“HYSt”
,
“modE”
,
“t on”
,
“toFF”
,
“unit”
and
“AL”
are connected with both “SEtP” and
“SEt2”
thresholds.
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 20).
If the power supply is interrupted, the device does not remember the status of relays selected using
the RS 485 interface.
Description:
A, B, C, D
points where measured signal exceeds border values (expected
value ± allowed deviation)
B
ON
,B
OFF
,D
ON
,D
OFF
relays state changes moments: (for
“t on”
> 0,
“toFF”
> 0)
tA , tB , tC , tD
time periods while input signal is in zone A or zone B
Fig. 20: Principle of LED/relay output operation for two thresholds mode
Displayed value
zone B
zone A
zone B
closed
open
time
time
time
time
time
open
closed
closed
open
open
closed
"toFF"
parameter
"toFF"
parameter
"toFF"
parameter
"t on"
parameter
"t on"
parameter
"t on"
parameter
measured
signal
"SEtP"
or
"SEt2"
parameter
"HYSt"
parameter
"HYSt"
parameter
relay state
(
modE
=
in
t on
= 0
toFF
= 0)
relay state
(
modE
=
out
t on
= 0
toFF
= 0)
relay state
(
modE
=
in
t on
= 0
toFF
= 0)
relay state
(
modE
=
out
t on
= 0
toFF
= 0)
