Emerson Rosemount 8750W Reference Manual page 83

Table 8-3:
Register value
253
(1) See
Pulse width
LOI menu path
Modbus register
The factory default pulse width is 0.5 ms.
The width, or duration, of the pulse can be adjusted to match the requirements of different
counters or controllers (see
1000Hz). The transmitter will accept values from 0.1 ms to 650 ms.
For frequencies higher than 1000Hz, it is recommended to set the pulse mode to 50% duty
cycle by setting the pulse mode to frequency output.
The pulse width will limit the maximum frequency output, If the pulse width is set too wide
(more than 1/2 the period of the pulse) the transmitter will limit the pulse output. See
example below.
Figure 8-1:
A
A.
B.
C.
D.
Example
If pulse width is set to 100 ms, the maximum output is 5Hz; for a pulse width of 0.5 ms, the
maximum output would be 1000Hz (at the maximum frequency output there is a 50%
duty cycle).
Reference manual
Pulse factor other units
Section 8.5.
Figure
Pulse Output
B
C
Open
Pulse width
Period
Closed
(continued)
Units
(1)
Special units
Detailed Setup > Output Config > Pulse > Pulse Width
329, 330
8-1). These are typically lower frequency applications (<
D
Advanced Configuration Functionality
79