Di Wiring; Digital Outputs; Table 3-3. Digital Input Characteristics - Emerson FB2100 Instruction Manual

Emerson FB2100 Flow Computer Instruction Manual
D301783X012
March 2019

Table 3-3. Digital input Characteristics

Type
Digital
Input (DI)
3.3.1

DI Wiring

The diagram below shows how to wire the digital input.
Figure 3-4. Digital Input (DI) Wiring [DI/DO/PI1 & DI/DO/PI2] – (CPU Option 2)
1
3.4

Digital Outputs

The FB2100 flow computer with CPU option 1 includes a single digital output. The FB2100 flow
computer with CPU option 2 includes two channels you can configure as digital outputs (DO),
digital inputs (DI) or pulse inputs (PI).
Note
When using a digital output to drive an inductive load (such as a relay coil), place a suppression
diode across the load. This protects the DO from the reverse Electro-Motive Force (EMF) spike
generated when the inductive load is switched off.
When configured as digital outputs, the channels have the following characteristics:
64
Number Supported
0 to 2 as follows under CPU option 2 only:
▪ 1 or 2 non-isolated channels on CPU
board (DI/DO/PI1 and DI/DO/PI2). Two
always present; you can configure one,
both, or neither as DIs.
Dry contact
Characteristics
▪ Circuit protection
▪ 30ms input filtering
▪ Maximum input frequency of 10 Hz
▪ Selectable current source of 66 µA or 2
mA
▪ Either externally driven or internally
driven and pulled to ground by dry
contact closures or open collector
devices
When a channel is configured as a DI it
▪
cannot be used as a DO or PI channel
I/O Configuration and Wiring