Emerson Site Supervisor, Руководство пользователя

Страница: 74 / 141

Utility Monitoring Software Overview
•
5
-
19
5.8.6 Performance Requirements
KWH Pulse Input
1. When configured for KWH pulse input, the
Demand Control application must detect 100% of
all pulses present on the input, as long as the
pulses occur no faster than 50 pulses/second
(PPS) and have pulse width of at least 20ms.
2. The local digital inputs on the controller are able
to support 50 PPS. Digital inputs located on
expansion modules (such as IPEX60) will not
support KWH pulse inputs.
5.9 Utility Monitoring
The Utility Monitoring application tracks the
consumption of metered services (such as electricity, gas,
and water) and monitors the usage or rate of usage of other
utilities such as door openings and door openings per hour.
The number of Utility Monitoring applications allowed
is based on the total number of applications allowed in the
controller. Additional applications may be added with a
separate license key.
5.9.1 Utility Usage Calculation
5.9.1.1 Utility Type
The user can specify the type of utility to monitor by
selecting an engineering unit that represents the type of
input connected. For example, if an analog rate signal
from a power meter is connected, the engineering unit will
be “KW.” Similarly, if a digital pulse signal from a water
meter is connected, the engineering unit will be “Liters.”
The controller will have the ability to calculate utility
consumption based on:
• Analog usage rate signal (for example, KW, GPM)
• Digital pulse input (for example, KWh, gallons/
liters, CCF)
• Analog Current/Voltage Input(s) - Single or Three
Phase (only used if monitoring power)
5.9.1.2 Analog Input
When an analog usage rate signal input is selected, the
application calculates energy consumption on a weekly,
daily, and monthly basis by integrating the instantaneous
power samples (approximation by finite steps). The
application considers a varying sampling frequency of the
input signal to produce an energy calculation.
5.9.1.3 Digital Pulse Input
When a digital energy pulse input is selected, the
application calculates energy consumption on a weekly,
daily, and monthly basis by accumulating the energy
pulses detected on the digital input. The digital input
supports energy pulse rates up to 50 pulses per second.
An instantaneous power output is also calculated. This
calculation uses the energy consumed over a one-minute
period to calculate the average power over the minute
period.
The Pulse Input displays the count of the number of
pulses it has received. The user will configure the Units
Per Pulse property so the algorithm knows what the pulse
represents.
5.9.1.4 Current/Voltage Inputs - Single/
Three Phase
When a current input is selected, the application
calculates energy consumption by calculating
instantaneous power and then integrating the power
calculation by finite step approximation. The application
supports a single current input for single phase
monitoring, or three current inputs for three phase
monitoring. Additional voltage and power factor inputs is
provided so that the power can be calculated. These inputs
can be set to fixed values, or can be driven by real-time
voltage and power factor outputs from a smart power
meter.
5.9.2 Consumption Totalizing
5.9.2.1 Totalizer Output
The Utility Monitoring application provides a totalized
output that accumulates while the quantity being measured
is consumed. The user can specify duration of logs in days
that the Totalizer Output will accumulate before it resets to
zero. The duration can also range from 1 minute to 24
hours. Before the automatic reset of the totalizer, the
application sends to the totalizer a maximum value
through a log.
NOTE: The Three Phase mode only applies if
the engineering unit selected is either KW or
KWh.