Emerson ROC827 instruction manual PI Module, Channel Per Active LED Maximum

ROC827 Instruction Manual

Table 3-11. Power Consumption of the High and Low Speed Pulse Input Modules

Power Consumption (mW)		Quantity	Duty	Sub-Total
I/O Module		Used	Cycle	(mW)
Description	PTYPICAL

PI Module

Channel 1

Channel 2

Per Active LED –

Maximum 4

Jumper set to +T @ 12 volts dc

Jumper set to +T @ 24 volts dc

21 mA @ 12 volts dc No	252 mW
Channels Active
7.4 mA	88.8 mW
7.4 mA	88.8 mW
1.5 mA	18 mW

1.25* Measured Current Draw at +T Terminal

2.5* Measured Current Draw at +T Terminal

Table Total

Duty Cycle The duty cycle is the time on divided by the total time, and is essentially the percent of time that the I/O channel is active (maximum power consumption).

Duty Cycle = [Active Time * (Signals Duty Cycle)] ⎟ (Total Time Period)

For example, if a Pulse Input receives a signal for 6 hours over a 24-hour time period and the signal’s wave form is on time for 1/3 of the signal’s period:

Duty Cycle = [6 hours * (1 ⎟ 3)] ⎟ (24 hours) = 0.0825

Issued Mar-06 Power Connections 3-17