The LocalTalk system is much less sensitive to power problems than many
networks.
To start with, LocalTalk uses differential signaling, which has a higher
noise immunity than normal, directly-connected TTL logic networks (like
Corvus, for instance). Also, LocalTalk uses transformer coupling from the
network to the node. This provides additional isolation from noise on the
network. The transformer specification requires that there be no
significant leakage current with 1000VDC applied between the secondary
winding and the core.
Because the LocalTalk network is passively coupled, any severe noise spikes
would have to come through the system itself. This means any protection
provided for the system itself would also be protecting the network.