DRAFT - 11 December 2014
DRAFT - 11 December 2014
INM MTL4850_54 Rev4
7
DRAFT - 11 December 2014
4.1.4
DC power connections
The HTP-SC32 has a removable, 4-way, screw-clamp terminal connector that provides
redundant 24V dc supply connections. LED indicators are provided to indicate the presence
of power to each of the redundant power inputs. A series diode in each supply input means
that the higher of the two voltage supplies is used and there is an automatic switch-over of
supplies if one fails. A 0.5A inline fuses protect against over current.
Power requirements:
Voltage: 20–35V dc
Current: 75mA @ 24V dc
Connect the dc power to the board as shown in Figure 4.3.
4.1.5
HART addressing
A 6-way DIP switch (SW1) is provided on the circuit board to enable a unique HART address
to be set for the HART multiplexer. The switch is binary coded and the relevant ‘bits’ should be
switched to the ON position. See Section 5.3.2 for additional information.
4.2 HMP-HM64 HART interface
Designed to be connected to remote connection units or backplanes via ribbon cables
the HMP-HM64 HART interface provides the user with an interface easily configurable
and expandable to meet system requirements. It accommodates two MTL4850/54 HART
multiplexer modules and is therefore capable of supporting 64 channels itself: it can also be
daisy-chained with others to support further channels on one serial RS485 link.
Figure 4.3
DC power
connections
Figure 4.4
HMP-HM64
connections