6.4.2 Cabling and Connection to Controller Reading Head Interface

6.4.2 Cabling and Connection to Controller Reading Head Interface

Depending on the type, the AMS measuring system can be provided with different mechanical interfaces, see also the SCHNEEBERGER MONORAIL and AMS product catalog. In principle, three different connector variants are available:

• A: S-type
• B: R-type
• C: M-type

Fig. 6.xx - AMS reading head assembly overview

SCHNEEBERGER recommends using the M-type connector as it can be mounted directly on the machine near the cable chain through the fixing holes in the mounting bracket. From here, for AMSA and AMSD, the connection to the controller connection point can be continued using the KAO 13 type extension cable.

For an overview of interfaces, extension and connection cables, please refer to the SCHNEEBERGER MONORAIL and AMS product catalog.

As a special implementation, the reading head interface can also be provided with a 0.17m long connection cable between the reading head and the electronics box.

Electronics Box

The electronics box of the reading head should be installed in a position that is easily accessible for maintenance. There is an LED here to display the operating status. Otherwise, it is important to ensure that the cables entering and leaving the box are tensioned after laying and have minimum bending radii (see below).

Cables

When laying measuring system cables, the following points must be observed:

• A 12-pin cable with a minimum cross-section of [4 x (2 x 0.14) + (2 x (2 x 0.5)] mm2 should be used as the extension and connection cable between the measuring system and the controller.
• Maximum cable lengths are:

• When using AMS with analog signals and interpolation and digitizing electronics SMEa, the specified cable lengths also apply, meaning a maximum of 30 m between the measuring system and SMEa, and a maximum of 50 m between SMEa and the controller.
• For cable conduits, observe the mounting bracket dimensions or connector diameter (Ø = 28 mm) in the catalog.
• Do not lay cables next to interference sources, such as magnetic fields from power supplies, main power lines, motors, valves, relays and their feeders. Sufficient distance from interfering cables can be achieved by observing the following:
  • A distance of 0.1 m
  • When using metal cable conduits, a grounded partition wall is required
  • Maintain a distance of at least 0.2 m from storage chokes in switched-mode power supplies
• Separate hydraulic hoses and cables.
• Lay reading head cables as statically as possible, e.g., do not route them in cable chains. Use extension cables for cable chains.


Fig. 6.xx - Reading head interface with cable chain

1 Reading head
2 Electronics box
3 Reading head cable
4 Extension cable
5 Cable chain (not included)
• Do not use conduits with sharp edges.
• Lay cables without any tensile load.
• Observe the bending radii of cables:

Cable Diameter	Permissible Bending Radius
	Alternating Bending	Single Bending
6 mm	> 75 mm	> 20 mm
8 mm	> 100 mm	> 40 mm

Shielding

The cables of the AMS measuring system are equipped as standard with shielding against electromagnetic interference fields. The shielding in the connection cable is connected to the controller via the connector housing. In addition to the cable shielding, the metal housings of the measuring system and drive controller also serve as shielding. These housings must exhibit exactly the same electrical potential. They must be connected to the protective ground conductor of the drive controller via the machine body or control cabinet. The cross-section of the equipotential bonding conductor must be at least 6 mm2 (Cu).

• Connect the housings of the measuring system and drive controller to the ground of the drive controller via the machine body and/or control cabinet.
• Connect the cable shielding of the connection cable directly to the drive controller, with the connector housing covering a large surface area and with the lowest possible inductance.

Note

• When there are connectors in the wiring path, avoid electrical contact between connectors (plugs) and other metal parts.
• To prevent grounding through metal housings, only use transmission lines with plastic-covered metal connectors.

Accessibility of Measuring System After Installation

For hard-to-reach axes, it is recommended to provide inspection openings on the machine to facilitate maintenance work on the measuring system. This way, the reading head as well as the connections between the reading head cable and extension cable should be easily accessible.