HeidenhainCH-4542Spindle Lubrication Control Unit (SLC) for High-Speed Motor Spindles — 24 V DC, 1.5 A, Controller Only

Product Description

What this part is

A Spindle Lubrication Control unit — SLC — for Step-Tec high-performance motor spindles, rated 24 V DC at 1.5 A. Step-Tec builds the motor spindles fitted to machining centres from a number of leading machine-tool manufacturers, and the SLC is the control element that supervises delivery of lubricant to the spindle bearings.

Correcting the source data — two errors, and one of them is the part number:
“CH-4542” is not a part number. It is a Swiss postal code: CH-4542 Luterbach, the town where Step-Tec AG has been located since 2000. It appears on the unit’s label as part of the manufacturer’s address. Our previous title carried it as if it identified the product, which would have sent anyone searching for it nowhere. The actual manufacturer part number is 15.10-1137-247, and that is now the leading number on this listing and in the model number field.

Second, our record gave the brand as Heidenhain and said the unit was “manufactured by Heidenhain in Germany.” That is wrong on both counts. This is a Step-Tec product, and Step-Tec AG is a Swiss company at Luterbach, part of GF Machining Solutions (the Georg Fischer group). Heidenhain is a separate German manufacturer of encoders and controls with no relation to this assembly. We have corrected the brand and manufacturer fields and removed the German origin claim.

Why the lubrication control is the part that protects the spindle:
This is the reasoning that makes an SLC worth its price, and it is worth setting out plainly.

A Step-Tec motor spindle runs its bearings at very high speed — the range spans roughly 10,000 rpm on the large HSK-A100 platforms to 42,000 rpm on HSK-E40 and 50,000 rpm on HSK-32 units. At those speeds the bearing lubrication regime is not a maintenance convenience, it is the thing keeping the bearings alive. Step-Tec offers three lubrication systems across the range and each has a speed ceiling: DOL (direct oil lubrication) up to about 20,000 rpm, CGL (continuous grease lubrication) up to about 18,000 rpm, and LGL (lifetime grease lubrication) up to about 12,000 rpm.

On a spindle using an actively delivered system rather than lifetime grease, the control that meters and monitors that delivery is a single point of failure for the whole spindle. Lose lubrication on a hybrid ceramic bearing at 20,000 rpm and you do not get a warning noise and a planned repair — you get a seized spindle and a rebuild costing many times the machine’s day rate. That is why plants running Step-Tec spindles hold an SLC on the shelf rather than ordering one when it fails.

Published data

Function: spindle lubrication control (SLC)Supply: 24 V DCCurrent: 1.5 AManufacturer part number: 15.10-1137-247Manufacturer: Step-Tec AG, CH-4542 Luterbach, Switzerland — part of GF Machining Solutions
That is the whole of what is published, and we are not going to pad it. Step-Tec does not release SLC datasheets publicly; the unit is supplied as part of a spindle package and documented in the machine builder’s manual rather than in a catalogue. Enclosure dimensions, mounting method, input and output signal definitions, connector pinout, alarm and interlock behaviour, oil pressure or flow thresholds, and which spindle platforms this specific variant serves are all unpublished. We have left those blank rather than infer them.

The photographs on this listing are therefore the specification: they show the housing, the labelling and the connectors. If a dimension or a connector detail decides your purchase, ask and we will measure and photograph the actual unit.

What is not included

The control unit only. Not included: the spindle itself, the oil or grease reservoir and pump, oil-air or minimal-quantity lubrication lines and fittings, the cable harness and mating connectors, the sensors it supervises, mounting hardware, and any machine-builder documentation or parameter set.

Quantity and configuration

Two units in stock, sold individually. On a machine-critical spindle spare that is a useful depth — one to fit and one to hold, or a spare each for two machining centres running the same spindle platform.

Interchange guidance

Search forms include 15.10-1137-247, 15101137247, 1510-1137-247, 15 10 1137 247, Step-Tec SLC, Step-Tec spindle lubrication control, and — because it is on the label and people do search it — Step-Tec CH-4542. Brand names buyers arrive under: Step-Tec, StepTec, GF Machining Solutions, Georg Fischer, GF AgieCharmilles, and Schaublin (which historically distributed Step-Tec spindles).

Before ordering, confirm the part number against your spindle’s parts list. Step-Tec spindles are supplied as platform-specific packages with common parts shared across a housing diameter, and an SLC variant matched to one platform may not carry the correct signal set for another. The full 15.10-1137-247 number, not the family, is what you need to match. Step-Tec remains a current manufacturer through GF Machining Solutions, so factory support for the number is available.