Siemens SIPART PS2 Compact Operating Instructions page 16

Two-wire mode
NOTICE
Connection of voltage source to current input
Device damage if a voltage source is connected to the current input I
● Never connect the current input I
● Always use a voltage source with a maximum output current of I = 20 mA.
Note
Improvement of interference immunity
● Lay signal cables separate from cables with voltages > 60 V.
● Use cables with twisted wires.
● Avoid getting too close to large electrical process cells.
● Use shielded cables to guarantee the full specification according to HART.
● Take account of the conditions specified in the technical data for HART communication.
4.1.1 Additional safety notes for PA and FF
If the bus shield is fully effective, the interference immunity and the interference emission conform to the specifications. The
following measures ensure that the bus shield is fully effective:
● The shields have been connected to the metallic connections of the positioner.
● The shields have been laid up to the terminal boxes, the distributor and the transceiver.
Note
Dissipation of glitch impulses/equipotential bonding
In order to dissipate glitch impulses, the positioner must be connected to an equipotential bonding cable (earth potential)
using a low resistance. The positioner in the Makrolon enclosure is therefore equipped with an additional cable. Connect
the this cable to the shield of the bus cable and the equipotential bonding cable using a cable clamp.
Devices in the stainless steel or aluminum enclosure have a corresponding terminal on the outer side of the enclosure.
This terminal must also be connected to the equipotential bonding cable.
For applications in hazardous areas, ensure an adequately suitable equipotential bonding between the hazardous and
non-hazardous areas.
The positioner is equipped with an additional input (terminal 81 [+] and terminal 82 [-]) to approach the safety position. After
activating this function, this input must be continuously supplied with +24 V in order to retain the normal control function.
If this auxiliary voltage fails or is switched, the exhaust air valve is forced-opened and the actuator moves to the defined
safety position so that the actuator cannot be moved using the buttons on the device and the master.
Communication with the master is still possible. The "Jumper" on the basic electronics is used to activate this function. It can
be accessed after removing the module cover, and must be switched from the right position (delivery state) to the left
position.
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to a voltage source, otherwise the positioner may be destroyed.
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(terminals 6 and 7).
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SIPART PS2 (6DR5...)
A5E03436620-04, 02/2014