Emerson EC20 Series User Manual page 18

12 Chapter 4 Product Specifications
4.7.5 Power Consumption Of Expansion Module
Model
EC20-0808ER
EC20-0808ET
EC20-4AD
EC20-4DA
EC20-4AM
EC20-4TC
☆: Refer to the power consumption when the analog output channel port connects with the output. If the current
output port (0~20mA) is not used, the current can be decreased to 50mA.
4.7.6 Power Capacity Calculation In Expansion Connection
Before the PLC connects with an expansion module, users should calculate the current sum of each power supply of
the expansion module, and ensure the current sum is less than the output current provided by the corresponding
power supply of the main module to avoids the over loading of the main module power supply.
Example 1: the main module is EC20-2012BR, at 25°C ambient temperature, two EC20-0808ET, two EC20-4AD,
one EC20-4DA and one EC20-4TC shall be connected to, verifying the feasibility.
Checking computations as following:
Power circuit
5V/GND
24V/GND
24V/COM
It is obvious that the total power consumption of above expansion module is less than the permission load of the main
module, and the designing scheme is feasible.
Example 2: the main module is EC20-3232BT, at 25°C ambient temperature, three EC20-0808ET, two EC20-4AD,
one EC20-4DA shall be connected to, using 20mA output port and one EC20-4TC.
Checking computations as following:
Power circuit
5V/GND
24V/GND
24V/COM
The sum of the 5V/GND power consumption of the expansion module is 440mA, it is larger than 350mA which is the
upper limit of 5V power supply; although the power consumption of 24V/GND and 24V/COM is less than the
permitted current of the main module, the designing scheme is unfeasible.
The solution to solve the insufficient of power supply capacity is to select the expansion module with self-carried
power source. It can power by itself, also its outputs of 5Vdc/GND, 24Vdc/GND, and 24Vdc/COM can power to the
expansion module added later.
4.8 Programming Tool Of User Program
ControlStar programming system provides the programming, up/down-loading, debugging and monitoring the user
program of the EC20 series PLC. The system also provides abundant help information, which can use ladder
diagram, instruction list and sequence functional diagram to program.
Table 4-11 Power consumption of each expansion module
5V/GND
30mA
80mA
50mA
50mA
50mA
50mA
Current provided by the main module
750mA
580mA
460mA
Current provided by the main module
350mA
650mA
360mA
EC20 Series PLC User Manual
Max. current consumption
24V/GND
50mA
0
0
0
0
0
Actual consumed current
(80×2+50×2+50+50) = 360mA
(0×2+0×2+0+0) =0 mA
(50×2+25×2+110+25) = 285mA
Actual consumed current
(80×3+50×2+50+50)=440mA
(50×3+0×2+0+0)=150mA
(50×3+25×2+120+25)=345mA
24V/COM
50mA
50mA
25mA
120mA
☆
90mA
☆
25mA
conclusion
Pass
Pass
Pass
conclusion
Un-passed
Pass
Pass