Siemens 1PH818, Operating Instructions & Installation Instructions

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5.8 Voltage supply “ 10 V DC ”
Voltage supply for external components, e.g. for a potentiometer for speed setting (PELV current
source according to EN 60204-1).
Connection:
“ 10 V ” - “ GND ” (max. load Technical data und connection diagram).
During an overload or short-circuit (10 V - GND), the control voltage (and thus the device) is
disconnected . Automatic start after elimination of the cause of error.
It is not permissible to connect outputs of several devices to each other!
5.9 Relay output “ K1 ” for fault indication
An external fault indicator is available over the potential-free contact of the built-in relays (max. contact
rating
Technical data and connection diagram).
For operation the relay is energized, connections “ 11 ” and “ 14 ” are bridged. For fault the relay is de-
energized.
Information
After switching on the line voltage, an initialisation time of a maximum 7.5 seconds is required for the
device's electronics to be operational. Subsequently, a reliable status message will be possible. If no
malfunction is detected, the relay will be energised after the initialisation time.
Since both line voltage
fl uctuations and ambient conditions affect the initialisation time, a different
delay might occur in individual cases.
5.10 MODBUS (RS-485) interface
Via the MODBUS interface (terminals “ A ” and “ B ” ) Siemens customer service can check the operating
state of the fan.
5.11 Potential at control voltage connections
The control voltage connections (< 50 V) relate to the joint GND potential (Exception: Relay contacts
are potential free). There is a potential separation between the control voltage connections and the
protective earth. It must be ensured that the maximum external voltage at the control voltage
connections cannot exceed 50 V (between
“ GND ” terminals and “ PE ” protective earth). If necessary, a
connection to the protective earth potential can be established, install bridge between “ GND ” terminal
and the “ PE ” connection (terminal for screening).
Assembly instructions ECblue Electrical installation
L-BAL-F065-GB 1617 Index 004 Part.-No. 00702801-GB
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