Heidenhain EQN1325.001-2048 Rotary Encoder: Complete Technical Guide and Applications

13 Ιανουάριος 2026

Historical parts record: Photos and notes below belong to this record. Confirm the offered unit’s full model, condition and available test evidence before ordering.

What is the HEIDENHAIN EQN 1325 rotary encoder?

The EQN 1325 is HEIDENHAIN's absolute rotary encoder with the EnDat interface — the encoder that tells a drive or control not just how far the shaft has turned but where it is right now, without homing. The photographed unit's nameplate states the full identity: EQN 1325.001 - 2048, V9, EnDat01, 5 V ±5%, Id.Nr. 312 214-03, S.Nr. 7 818 750 C, HEIDENHAIN, 101 Traunreut · Germany. The intake paperwork books three purchases of this type — two of Id.Nr. 312 214-16 and one of 312 214-03, one unit each — while the photo set documents the 312 214-03 unit (S.Nr. 7 818 750 C); the source list repeats the same frames across the entries, so the repeated angles below are kept as archived. All nameplate facts and the inspection video below are read from these photos.

3 min readContent reviewed 8 October 2026

Part details

EQN 1325.001-2048, as read from the nameplate and the construction
Field	Value
Brand	HEIDENHAIN — 101 Traunreut, Germany
Model	EQN 1325.001 - 2048 (nameplate), version V9
Interface	EnDat01, supply 5 V ±5% (nameplate)
ID number	Id.Nr. 312 214-03 (photographed unit); intake also books two units of 312 214-16
Serial	S.Nr. 7 818 750 C with barcode (photographed unit)
Shaft	Solid shaft with threaded centre hole, sealed bearing seat
Mounting	Stainless three-arm stator coupling bracket with slotted ears, clamp band with two screws
Cable	Side-exit through the cast metal cover, long free tail
Inspection	Chinese workshop inspection sticker on the housing
Quantity	Three intake bookings, one unit each (2 × 312 214-16, 1 × 312 214-03); photo set covers one unit

Scroll sideways to see the full table.

Values are read from the nameplate and the photographed construction in the photo set.

What absolute means on a shaft

An incremental encoder counts steps and forgets them at power-off; an absolute encoder like the EQN 1325 reads the shaft's position directly from its code disc every time it powers up, so the axis knows where it is before the first motion. The EnDat interface is HEIDENHAIN's bidirectional protocol over that same cable: the encoder gets its 5 V supply (the nameplate allows ±5%) and returns the absolute position value digitally — no quadrature counting, no reference run. On retrofit and repair work this is the property that matters: bolt the encoder on, power up, and the axis is positioned with no homing cycle, which is why the EQN 1325 family shows up on machine-tool feeds, rotary tables and printing or converting lines where losing position costs setup time.

Mechanically the unit photographed is the solid-shaft build: a stainless three-arm bracket holds the housing by its clamp band and takes up mounting tolerance through the slotted ears, while the shaft rides in a sealed bearing seat with a threaded centre for the fixing screw — no separate coupling to align. The cable leaves through the cast cover at the side, which keeps the bend radius clear of the bracket. The three intake bookings on this type, two under Id.Nr. 312 214-16 and one under 312 214-03, sit one model digit apart in HEIDENHAIN's ID scheme; the photographed serial 7 818 750 C belongs to the 214-03 unit, and its nameplate, bracket and shaft are all shown in the photos below.