WHDG30101G 10/100BASE-TX LAN Transformer

Three 10/100 ports.

The internal structure settles it: the WHDG30101G holds six 1CT:1CT units in three groups, giving each port two channels — one pairset. One pairset per port is the 100M port structure; a Gigabit port needs four channels across two pairsets, so three Gigabit ports would require twelve units. Counting transformer units is a more reliable check than reading the part number: a 100M part carries twice the port count in units, a Gigabit part four times. Gigabit options are listed in the 100/1000 BASE-T range.

Every electrical figure matches, and so do the outline and hole pattern; what differs is the internal running order — the transformers and common-mode chokes sit on opposite sides of the schematic on the two parts.

Both the WHDG30101G and the WHDG30102G measure 32.00 × 12.50 mm with 7.50 mm Max height, 2.00 mm pitch, 10.16 mm row spacing and a 28.00 mm span, and every electrical item is identical. So there is no performance comparison to make between them. What does need checking is row spacing: the other triple-port part in the 10/100 BASE-T range uses 8.50 mm and will not drop into the same holes.

Not advisable. The WHDG30101G is rated 0 °C to +70 °C — a commercial temperature grade whose cold end stops at 0 °C.

Outdoor enclosures, unheated plants, vehicles and rail applications all see sub-zero temperatures and need a part rated down to -40 °C. Storage temperature is quoted as -40 °C to +85 °C, but that is the unpowered limit and must not be read as an operating range. The WHDG30101G also does not support PoE, so the ports have to be powered locally. Wide-temperature options are listed in the 10/100 BASE-T range.