The 3-wire AI Fused Injected Power Terminal Block

is designed for 3 wire analog transmitters and can be

used with the AI 4-20mA HART CHARM. The field power is

supplied from the injected power bus on the baseplate,

but the power is not removed from the field device when

the AI CHARM is removed from the baseplate. There is

a Green LED on the terminal block that indicated power

is supplied to the field and the 2A fuse also functions

as a means to disconnect power from the field device.

Although this terminal block was introduced in 2017. it

is backwards compatible to any version of DeltaV with

Electronic Marshalling.

Although any signal type can be installed in any location on

the CHARM baseplates, it is recommended that AC voltage

circuits be separated from low voltage signals to comply

with safety recommendations and to mitigate induced noise

in the signals. Standard Terminal blocks, Fused Injected

Power terminal blocks and Relay Output Blocks can be used

on the same carrier, typically, to allow the use of DO 24V

DC isolated CHARMs on higher wattage and 3-wire devices

alongside of standard 24V DC instrumentation signals or

relay contacts.