Emerson ROC827 - Manual (Page 62)

ROC827 Instruction Manual
Issued Mar-06 Power Connections 3-18
Table 3-12. Power Consumption of the MVS Modules
Power Consumption (mW)
I/O Module
Description P
TYPICAL
Quantity
Used
Duty
Cycle
Sub-Total
(mW)
MVS Module 112 mA @ 12 volts dc 1344 mW
Per Active LED – Maximum 2 1.5 mA 18 mW
Power provided by the module
for the MVS sensors
1.25 * Measured
Current Draw at +
Terminal
1
Table Total
Note: For an MVS sensor, the typical mW per MVS is about 300 mW.
Duty Cycle The duty cycle is the time on divided by the total time. For an MVS,
the sensor is always drawing power, so enter the duty cycle as “1” for
the MVS power calculations. The LEDs can also have an associated
duty cycle, which is essentially the percent of time that the LEDs are
active.
Duty Cycle = Active time
÷ (Active time + Inactive time)
For example, if the LEDs are on approximately 20 minutes a day:
Duty Cycle = 20 minutes
÷ (24 * 60 minutes in a day) = 20 ч 1440 = 0.014