Switched-mode power supply module with AC and DC supply
The MDS90A switched-mode power supply module can be used in combination with an MDP92A-..power supply module with controlled DC link voltage. If a separate line connection is used instead of the supply via the +UB signal of the MDP92A-.., an NC contact contactor must be provided in the supply system cable.
When the switched-mode power supply module is combined with an MDP90A-.., MDR91A or MDR90/91B-.. module, the NC contact contactor is not required.
The following requirements apply to the NC contact contactor:
Requirement | Value |
|---|---|
Nominal voltage | Nominal line voltage |
Nominal current | ≥ 6 A |
Fall time (closing) with omission of the 24 V control | < 22 ms |
Overvoltage protection for coil voltage required? | Yes |
Utilization category | AC3 |
Required coil voltage | 24 V |
The electrical service life must also be taken into account when selecting an AC contactor with regard to the required switching frequency. Depending on the application, regular maintenance is required.
An NC contact contactor is actuated via plug-in contact X19 if the power supply unit is operated with a sufficient DC supply from the DC link. This NC contact contactor disconnects the power supply unit from the AC supply cable so that it is disconnected from the grid for EMC reasons. The NC contact contactor is not suitable for safely de-energizing the axis block.
The connection is displayed in the following wiring diagram:
[1] | Line contactor (NC contact contactor) |
DC link voltage | Voltage at X19 |
|---|---|
≥ DC 218 V (increasing) | 24 V |
≤ DC 200 V (decreasing) | 0 V |
When using a line contactor, you must at least use a capacitor module MDC90A-0120-.. as storage.
In addition, from a DC link voltage of ≤ 200 V, only the switched-mode power supply module may be supplied and no other consumers may be active in the DC link. Otherwise the reliable changeover without any interruption of the 24 V output voltage cannot be guaranteed.
