PDU calculator: how many servers per PDU

Enter the PDU input and your server's measured peak draw. The answer is the lower of the power limit and the outlet limit.

How it works

Usable power = volts × amps (× 1.732 for three-phase), × 0.8 if you load to 80% of the breaker. With A/B feeds each PDU must be able to carry the whole rack alone, so the power limit is counted against one PDU. Full explanation and a worked example: how many servers per PDU.

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<iframe src="https://rackmatch.net/embed/pdu-calculator/" width="100%" height="560" style="border:1px solid #ccc;max-width:560px" title="PDU calculator by RackMatch" loading="lazy"></iframe>

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