Project planning of the 24 V supply
Check whether the available current from the 24 V switched-mode power supply is sufficient for the total current demand of all consumers.
- Sum up the typical current demand of all consumers according to the following table:
Consumer | Current demand in mA | ||
|---|---|---|---|
1 | Basic demand
| Size 2/2E | 450 |
Size 3 | 500 | ||
Size 3E | 550 | ||
2 | Demand | DSI.. | – |
DFC.. | 100 | ||
3 | I/O option
| CID21A (/ODA) | 20 |
CIO21A (/OAA) | 60 | ||
4 | Safety sub-function | STO | – |
STO and CES.. | 35 | ||
CS..A | 180 | ||
5 | External fanOnly for products with nominal output currents of 46 A and 62 A. For products with a nominal output current of 32 A, the external fan is present depending on the project planning. | 300 | |
6 | Option of expanded temperature range /C.2 | 60 | |
7 | CBG.. keypad | 50 | |
8 | Connected periphery (encoder, sensors) | Max. 500 mA per M23 plug connector | |
9 | Connected safe periphery | Max. 180 mA per M12 plug connector | |
10 | Digital outputs (DO) | Max. 50 mA per output | |
11 | Safe digital outputs (F-DO) | Max. 150 mA per output | |
12 | Connected 24 V brake | Depending on the motor design | |
- Compare the total current demand of all consumers with the available current from the internal 24 V switched-mode power supply:
Power section | Available current | |
|---|---|---|
No internal switched-mode power supply | MPI90.. | – |
80 W switched-mode power supply | MPI91.. | 3.3 |
180 W switched-mode power supply | MPI92.. | 6.6 |
If the total current demand of all consumers is greater than the available current from the internal 24 V switched-mode power supply, you must supply the drive unit with 24 V externally. Supplying the drive unit with 24 V externally is always possible. If an external 24 V backup voltage is applied, SEW-EURODRIVE recommends the device design without an internal 24 V switched-mode power supply (MPI90A..).
When using an internal 24 V switched-mode power supply with simultaneous external connection of a 24 V and 400 V supply, note that the backup current of the external 24 V supply typically only takes over the full load at 26 V. Between 24 V and 26 V, the 24 V sources operate under partial load, depending on the load. If there is no 400 V supply connected to a device with an internal 24 V switched-mode power supply, the external 24 V supply is placed under full load.
