Specifications

ProLinx Communication Gateways, Inc. 77
HART Master Protocol Drive Manual
August 17, 2004
Appendix B – ProLinx HART Field
Connections
HART field instruments are divided into four categories; A through D, depending on
power requirements and whether the device sinks or sources a bias or operating current
from the network. The following table defines the categories:
Type Description
A Type A field instruments sink direct current from the
network and receive operating power from the network.
B Type B field instruments sink direct current from the
network but receive no operating power from the
network.
C Type C field instruments source direct current to the
network and receive no operating power from the
network.
D Type D field instruments neither source nor sink direct
current from the network, nor receive operating power
from the network.
On a given network, A, B, and D devices may be combined. C and D devices may also
be combined. A or B field instruments should not be combined with C devices.
Network Power Supply Requirements
Type Network Power Supply
A Required
B Required
C Must not be used.
D Not required, but may be used.
Note: The ProSoft 4107/4207 HART interface may be used with any HART field device.