TITANUS
SUPER·SENS
®
Installation
TSS_05_A-en-e Data:
02/09
5
– 7
5.4 Installation of the reset board
As an option the reset board can be installed into TITANUS
®
. If several
TITANUS
SUPER · SENS
®
are connected to one detection line the reset
board is only installed into the last device on the detection line (refer to
5H
Fig. 5.4).
The reset board can only be used if the quiescent current of the detec-
tion line is at least 5 mA and if the end of the detection line is an ohmic
resistor.
End of line resistor
The reset board replaces the detection line resistor. It is re-calculated
and is installed on the reset board (connector X1, refer to
6H
Fig. 5.4). The
value of the end of line resistor R
ER
is to be calculated as follows:
(
)
R
U
V
I
ER
L
R
=
−
2 7
,
where R
ER
= end of line resistor on the reset board in
Ω
U
L
= line voltage in V
I
R
= quiescent current of the line in [A]
Quiescent
current
of the line
The quiescent current I
R
of the line is to be calculated as follows:
I
U
R
R
L
E
=
where R
E
= original end of line resistor in
Ω
U
L
= line voltage in V
I
R
= quiescent current of the line in [A]
The formulas to calculate the end of line resistor and the quiescent cur-
rent of the detection line consider the ideal state of the signal evaluation.
If acknowledgement is not possible by means of the calculated end of
line resistor of the reset board the value of the end of line resistor is to be
reduced by about 20%.
INSTRUCTION