Does the 450M have reverse polarity safeguarding built in for power?

Does the 450M have protection built in for reverse polarity for mishaps when connecting power to the units? A client of mine lost 2 radios due to this.

The 5 GHz and 3 GHz 450m radios are powered differently (via PoE and DC respectively).

The 3 GHz 450m has a completely isolated supply, and can be connected using +48 or -48 VDC.

Which radios did the client you refer to lose? How were they connected?

Attached please find a guide to the power connections for 3 GHz 450m:
cam-10189_000v002.pdf (401.4 KB)