User Manual

Voltage input
Voltage inputs process 0...+10 VDC signals.
Input voltage: U = 0…10 VDC
Electrical values
Input impedance: approx. 100 kΩ
Resolution: up to 12 bit (default 10 bit)
Current input
In the case of current inputs, a 100 Ω shunt must be connected externally in parallel to
the universal input. Current measurement is performed indirectly via a voltage
measurement across the shunt.
Input current: I = 0…20 mADC (4…20 mADC)
Electrical values
Input impedance: 100 Ω
Resolution: up to 12 bit (default 10 bit)
Temperature input
Temperature inputs provide for connection of passive, temperature-dependent resistors
with a resistance value of approx. 4.5 kΩ, such as Pt1000/Pt100/Ni1000 elements and
NTC/PTC elements.
Temperature measurement is performed indirectly via resistance measurement. The
temperature value is determined in the software via resistance/temperature
characteristics.
Electrical values
Sensor current: I = 400 µA
Measuring range: 0…approx. 4.5 kΩ
Resolution: up to 12 bit (default 10 bit)
Digital input
Digital inputs are used to interrogate static switching states. The maximum input
frequency must not exceed 2 Hz.
Only floating contacts must be connected. The contacts are interrogated with approx.
24 V / 4.5 mA.
4.5 Real-Time Clock
SAPHIR is equipped with a real-time clock. It supports the following functions:
• Time indication in hours/minutes/seconds
• Calendar with leap-year
• Manual winter/summer time changeover
• Day of week
The real-time clock is buffered against power failure for at least two days. The clock
information is retained during this period.
Afterwards, the clock must be set manually (via HMI or PC).
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Siemens Building Technologies Hardware Description CE2P3689en
HVAC Products Hardware 25.11.2004