Schneider Electric 4000 Demand Synch Pulse Input, in -Metering Capabilities for more about demand

Chapter 5—Input/Output Capabilities	63230-300-212
Demand Synch Pulse Input	April 2001
DEMAND SYNCH PULSE INPUT	You can configure the circuit monitor to accept a demand synch pulse from
	an external source such as another demand meter. By accepting demand
	synch pulses through a digital input, the circuit monitor can make its demand
	interval “window” match the other meter’s demand interval “window.” The
	circuit monitor does this by “watching” the digital input for a pulse from the
	other demand meter. When it sees a pulse, it starts a new demand interval
	and calculates the demand for the preceding interval. The circuit monitor
	then uses the same time interval as the other meter for each demand
	calculation. Figure 5–1illustrates this point. See “Synchronized Demand” on
	page 59 in Chapter 4—Metering Capabilities for more about demand
	calculations.
	When in demand synch pulse operating mode, the circuit monitor will not
	start or stop a demand interval without a pulse. The maximum allowable time
	between pulses is 60 minutes. If 66 minutes (110% of the demand interval)
	pass before a synch pulse is received, the circuit monitor throws out the
	demand calculations and begins a new calculation when the next pulse is
	received. Once in synch with the billing meter, the circuit monitor can be used
	to verify peak demand charges.
	Important facts about the circuit monitor’s demand synch feature are listed
	below:

•Any installed digital input can be set to accept a demand synch pulse.

•Each system can choose whether to use an external synch pulse, but only one demand synch pulse can be brought into the meter for each demand system. One input can be used to synchronize any combination of the demand systems.

•The demand synch feature can be set up from SMS. See the SMS online help for instructions on device set up of the circuit monitor.

Normal Demand Mode	External Synch Pulse Demand Timing
Billing Meter	Billing Meter
Demand Timing	Demand Timing
	Utility Meter
	Synch Pulse
Circuit Monitor	Circuit Monitor
Demand Timing	Demand Timing
	(Slaved to Master)

Figure 5–1: Demand synch pulse timing

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