Emerson Micro Motion 3711, Configuration And Use Manual, Page: 87 / 234

Configuration and Use Manual 79
Configuring I/O
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In operation, the discrete output’s On period will be calculated from the values configured for discrete
output scaling plus the configured EU Value. The formulas used for calculation are as follows:
For a flow rate of 100 MCF, the discrete output’s cycle has the following form:
• ON for 4 seconds
• OFF a minimum of 8 seconds
For a flow rate of 650 MCF, the discrete output’s cycle has the following form:
• ON for 9 seconds
• OFF a minimum of 3 seconds
If the calculated On period is equal to or greater than the cycle time, the Off period is set to one
second. Be sure to set the TDO parameters so that cycle time is always greater than the calculated On
period.
7.9 Configuring pulse inputs
You need to configure pulse inputs if the Model 3711 was purchased with the I/O option, and you
configured the I/O terminals for one or two pulse inputs. You may need to configure one or two pulse
inputs.
To configure a pulse input:
1. Click
Configuration > I/O > PI Points
. The Pulse Input dialog box, containing three panels, is
displayed. See Figure 7-13.
Figure 7-13 Pulse Input – General panel
EUSpan HighReadingEU LowReadingEU
–
=
CountSpan 100%Count 0%Count
– =
OnPeriod
ConfiguredEUValue CountSpan
×
EUSpan
-----------------------------------------------------------------------------
0%Count
+ =