Emerson FB2100 Flow Computer Instruction Manual
D301783X012
March 2019
I/O Configuration and Wiring
67
3.5
Pulse Inputs
The FB2100 flow computer with CPU option 2 includes two channels that can be individually
configured as either pulse inputs (PI), digital inputs (DI), or digital outputs (DO).
When configured as pulse inputs, the PI channels have the following characteristics:
Table 3-5. Pulse Input Characteristics
Type
Number Supported
Characteristics
Pulse
Input (PI)
0 to 2 as follows (CPU option 2 only):
▪
1 or 2 non-isolated channels on CPU
board (PI/DI/DO1 and PI/DI/DO2). Two
always present; you can configure one,
both, or neither as PIs.
▪
Supports dry contacts and open
collector outputs connected to ground
and voltage inputs
▪
Supports single pulse for volume or
mass
▪
Input filtering selectable at 30 µs or 1
ms
▪
Frequency range from 0 to10.5 KHz
▪
Maximum input frequency for the 1 ms
filter is 300 Hz
▪
When a channel is configured as a PI it
cannot be used as a DI or DO channel
▪
ON when greater than 3.0V; OFF when
less than 2.0V
3.5.1
PI Wiring
The diagram below shows how to wire the pulse inputs.
Figure 3-7. Pulse Input (PI) Wiring [DI/DO/PI1 & DI/DO/PI2]- (CPU Option 2)
1
Open Drain Type or Open Collector Device (Externally Powered)
