Rockwell Automation 1404-M4_M5_M6_M8 Powermonitor 3000 User Manual, Firmware rev. 3.0 or LATER - Manual (Page 52)

52 Publication 1404-UM001F-EN-P - November 2009
Chapter 3 Powermonitor 3000 Unit Operations
Demand Setup
You may configure the demand period length, the number of demand
periods to average for demand calculation, the forced demand delay
and the type of calculation used for projected demand.
Demand Period Length sets the length in minutes (1…99) of the
demand period used for demand and projected demand calculation.
Range –99…99, default 15.
•
A positive value (other than 0) configures the power monitor to
use its internal clock to measure the demand period.
•
A setting of zero (0) configures the power monitor to use an
external synchronizing method to synchronize the demand
interval.
•
A negative value configures the power monitor to use its
internal clock for calculating projected demand and an external
synchronizing method to calculate actual demand.
External synchronizing methods include:
•
A dry contact end-of-interval pulse connected to status input #2
•
For Ethernet network units, a network demand sync broadcast
message from a network demand master power monitor or a
controller command message from a PLC controller.
Refer to Network Demand / Time Configuration on page 55 for more
informatin on network demand synchronization.
Number of Demand Periods specifies how many demand intervals are
averaged together to a floating window demand calculation. For
instance, to configure a 30 minute floating window, specify 2 as the
demand period length and 15 as the number of demand periods.
Range 1…15, default 1.
Forced Demand Delay is a timeout setting that waits for x number of
seconds before ending a demand period when the external demand
sync input function is being used. When a missed external demand
sync is detected the unit:
•
forces an end to the current demand period.
•
records an event log record of the event.
•
records a trend log record if the trend log interval is set to -1.
(Sync with demand setting)
TIP
In RSEnergyMetrix RT software and RSPower software, a negative
demand interval is set by checking a checkbox entitled ’Use Status
Input #2’ or ’Enable External Demand Sync’.