Assembling the M7-400
8-7
S7-400 and M7-400 Programmable Controllers Hardware and Installation
A5E00069481-04
With the details from the individual data sheets, you can calculate Current
Consumption I in this rack as follows:
Table 8-4
Calculation Example for Power Supply Module
Module
Slots
Occupied
+5 VDC
(Max. Current Consumption Values)
I / Module
I Total
CPU 488-3
2
4500 mA
4500 mA
IF 962-VGA
600 mA
600 mA
IF 962-COM
100 mA
100 mA
EXM 478
1
200 mA
200 mA
IF 961-DIO
85 mA
170 mA
IF 961-AIO
85 mA
85 mA
MSM 478
1
1000 mA
1000 mA
ATM 478
1
120 mA
120 mA
Short AT Module (LAN)
1400 mA
1400 mA
SM 431; AI 16 x 16 bits
3
700 mA
2.100 mA
SM 421; DI 32 x 34 VDC
3
30 mA
90 mA
SM 422; DO 32 x 34 VDC
3
200 mA
600 mA
IM 460-0
1
110 mA
110 mA
Total
15
10075 mA
From the data in Table 8-4, you see that to cover the current consumption
calculated here, you must install a power supply module PS 407 20A (for a
120/230 VAC supply) or PS 405 20A (for a 24 VDC supply) in the rack.
Note
If you wish to connect an expansion rack to the central rack via a send IM with
current transfer, you must take into account the current consumption of this
expansion rack when choosing the power supply module.