Basic Network - MAGSYS IGM11 Operating Instructions Manual

Industrial Gaussmeter IGM11 Operating Instructions
Chapter 9 Serial Interfaces
9.3.2 EIA-485 Basic Network
If none is transmitting, all senders are high-ohmic. Without termination, there will be
an undefined potential on the bus. To have a positive signal level, the bus will be
switched with a basic network.
The basic network should be provided for those devices with active bus terminal.
With the IGM11 the resistances of the basic network can also be mounted in the
connector casing. The 5 V connection provided for the basic network at Pin 8 of the
connector J4 can thus be loaded with a maximum of 50 mA.
Figure 23 EIA-485 Basic Network and Bus Terminals with Internal Connection
Figure 24 EIA-485 Basic Network and Bus Terminal with External Connection
MAGSYS
Resitance against power supply
Bus terminal resistance
Resistance against ground
Resistance against power supply
Bus terminal resistance
Resistance against ground
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