Pepperl+Fuchs PS1000-A6-24.20, Техническая информация

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Power Supply PS1000-A6-24.20
Application Notes
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26.5 Parallel Use for Redundancy
1+1 Redundancy
Devices can be paralleled for redundancy to gain higher system availability.
Redundant systems require a certain amount of extra power to support the load in case
one device fails. The simplest way is to put two devices in parallel. This is called a 1+1
redundancy. In case one device fails, the other one is automatically able to support the load
current without any interruption. It is essential to use a redundancy module to decouple
devices from each other. This prevents that the defective unit becomes a load for the other
device and the output voltage cannot be maintained any more.
1+1 redundancy allows ambient temperatures up to +70°C.
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using
multiple devices.
Recommendations for building redundant power systems:
• Use separate input fuses for each device.
• Use separate mains systems for each device whenever it is possible.
• Monitor the individual devices. Therefore, use the DC-OK signal of the device.
• It is desirable to set the output voltages of all devices to the same value (± 100mV)
or leave it at the factory setting.
• Set the devices into Parallel Use mode.
N+1 Redundancy
Redundant systems for a higher power demand are usually built in a N+1 method.
E.g. four devices, each rated for 20A are paralleled to build a 60A redundant system.
Pay attention that leakage current, EMI, inrush current, harmonics will increase when using
multiple devices.
Keep an installation clearance of 15mm (left / right) between two devices and avoid installing
the devices on top of each other.
Do not use devices in parallel in mounting orientations other than the standard mounting
orientation or in any other condition, where a reduction of the output current is required.
For N+1 redundancy the ambient temperature is not allowed to 60°C.