Advanced Installation Details; Hardware Switches - Emerson Rosemount 8750W Reference Manual

6

Advanced installation details

Topics covered in this chapter:
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6.1

Hardware switches

The electronics are equipped with two user-selectable hardware switches. These switches
set the Transmitter Security and Internal/External Pulse Power.
6.1.1 Transmitter security
The SECURITY switch allows the user to lock out any configuration changes attempted on
the transmitter.
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The switch is in the OFF position when the transmitter is shipped from the factory.
Note
The flow rate indication and totalizer functions remain active when the SECURITY switch is in either
position.
6.1.2 Internal/external pulse power
The pulse loop can be powered internally by the transmitter or externally or by an external
power supply. The PULSE switch determines the source of the pulse loop power.
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The switch is in the EXTERNAL position when the transmitter is shipped from the factory.
6.1.3 Changing hardware switch settings (field mount)
Note
The hardware switches are located on the top side of the electronics board and changing their
settings requires opening the electronics housing. If possible, carry out these procedures away from
the plant environment in order to protect the electronics.
Reference manual
Hardware switches
Additional loops
When the security switch is in the ON position, the configuration can be viewed but
no changes can be made.
When the security switch is in the OFF position, the configuration can be viewed and
changes can be made.
When the switch is in the INTERNAL position, the pulse loop is powered internally by
the transmitter.
When the switch is in the EXTERNAL position, a 5–28 VDC external supply is
required. For more information about pulse external power, see
Advanced installation details
Section 6.2.1.
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