Allen-Bradley 825-P, Руководство пользователя

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90 Rockwell Automation Publication 825-UM004D-EN-P - November 2012
Chapter 6 Configuring Protection & Logic Functions
The 825-P provides an ability to control external devices based on parameter
Load Control Selection. You can select Current, Power, or Thermal Capacity
Utilized to operate auxiliary outputs.
When the selected parameter exceeds the level set by Load Control Upper for one
second, the assigned auxiliary relay operates. The auxiliary relay resets when the
parameter drops below the upper level setting for one second.
When the selected parameter drops below the level set by Load Control Lower
for 1 second, the assigned auxiliary relay operates. The auxiliary relay resets when
the parameter is above the lower-level setting for 1 second.
You can use this feature to control the motor load within set limits.
I/O Configuration Analog Output
The expansion I/O option provides a 4
…
20 mA DC analog current output with
a variety of output parameters. Use the Analog Output Select setting to select a
parameter from the list of available options. Table 36 shows description and
scaling of the output for different parameter selections.
NOTE: Prompt of settings LD CTL UPPER and LD CTL LOWER are dependent on the LD CONTROL SEL
setting. All possible prompts are shown in Table 34.
NOTE: In addition to setting the Load Control levels, you must assign LD CTL UPPER and LD CTL
LOWER to auxiliary output relays (one each); see Table 43, and Figure 16
for connection
diagrams.
Table 35 - I/O Settings
Setting Prompt Setting Range Factory Default
ANALOG OUT SEL LOAD_I, AVG_I, MAX_I, %THERM, WDG_RTD, BRG_RTD, PWR_kW, PF LOAD_I
Table 36 - Scaling of Analog Output
ANALOG OUT SEL
(AOPARM)
Description Output Scaling (4 mA) … (20 mA)
(Unit)
LOAD_I Average Load Current 0.0…1.0 Per Unit of FLA
AVG_I Average Load Current 0.2…2.0 Per Unit of FLA
MAX_I Maximum of the Phase currents 0.2…2.0 Per Unit of FLA
%THERM Percentage Thermal Capacity 0…100%TCU
WDG_RTD Hottest Winding RTD Temperature 0…250°C
BRG_RTD Hottest Bearing RTD Temperature 0…250°C
PWR_kW Motor Power 0.0…1.0 per unit FLVA
PF Motor Power Factor 0.8 Lag…0.8 Lead