These optional LAN modules for the HFE series of 1600- and 2500-W rack-mounted, hot-swap power supplies allow remote monitoring, status check and programming through a number of standard protocols, supporting virtual instrument software architecture (VISA). The modules plug into any open slot on the standard HFE1600 or HFE2500 19-in racks, measuring the same size as the HFE1600 or HFE2500 I2C/PMBus-equipped power supplies. Removal or insertion of the modules can be made with the ac input applied (to the HFE rack housing, HFE1600-S1U or HFE2500-S1U) without causing any disruption to the power supply output voltage.