Siemens FS720 Mounting & Installation page 66

Mounting and installing extinguishing control panels
6
Card cage connections (1 sector exting.) FCA2046
66 | 248
Building Technologies
Fire Safety
Monitored output type LOAD
Use
Monitoring polarity
Monitoring
Calibration
2-way monitoring
Total load resistance, incl. cable
Max. cable resistance
Monitoring tolerance
OUT_MON+
OUT_MON-
A maximum of 10 electromagnetic valves can be switched in parallel.
In some applications, valves are used with blocking diodes as polarity protection.
Calculation of the cable resistance:
OUT_MON_+
(Rbox)
OUT_MON_-
Step 1: calculate the critical cable resistance
RcableCrit = (24.8 V – UloadMin) / ILoadMin
RcableCrit Critical cable resistance [Ω] at which a fault is still displayed and
the voltage at the load is still supplied to a sufficient extent.
ULoadMin Minimum voltage [V] at load, as per data sheet.
ILoadMin Minimum current [A] due to load at min. voltage, as per data sheet.
Valves, etc.
Normal polarity
Only in inactive state
Yes
Permitted
● 14...1000 Ω, max. 2 A
● 14...780 Ω with 2-way connection box
80 Ω, both lines
● ± 33 % at ≤ 200 Ω
● ± 16 % at > 200 Ω
● ± 2.5 % dynamic
n
1
Electromagnetic
actuator
Rcable
Uload Rload
A6V10210390_m_en_--
2018-08-29