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PHS1 servo head

PHS1 is designed to meet the arduous requirements of 'body-in-white' measurement, where fine angular position and long reach are needed.

PHS1 servo positioning head

The PHS1 servo positioning head features continuous servo drive in two axes, enabling the probe configuration to be positioned at almost any angle.

The PHS1 head is not locked into position in the same way as a PH10 PLUS indexing head. Instead it is driven to approximately the required position and, when a probing point is taken, the axes of the head latch simultaneously with the axes of the CMM to give accurate measurements.

The PHS1 head is controlled directly from an interface card in the CMM controller. Full information is given in the PHS1 programmers' guide.

A range of different probes can be fitted and automatically exchanged. These include touch-trigger probes, contact scanning probes and optical measurement probes.

Extra long extensions allow the Renishaw trigger probes to reach normally inaccessible features.

The head is protected by a built-in overtravel protection unit which signals the machine to stop in the event of a collision.

Operating temperature 

15 °C to 40 °C (50 °F to 104 °F)

Weight *

< 3 kg (<6.61 lb)

Carry capability

Combined probe and extension mass of 1 kg (2.2 lb)

Maximum torque

2 Nm

Mechanical clutch slip

3 Nm ±0.5 Nm

Movement speed

150 °/s maximum, 120 °/s typical

Arm rotation angle

D-axis: ±184°

E-axis: ±184°

Angular resolution

0.2 arc second (equivalent to 0.1 µm at 100 mm radius)

Collision protection

Signal for head protection and kinematic overtravel unit

Suitable head interface

PC interface card

Changer rack system


* including probe extension and kinematic joint


PC interface card

The PHS1 head is controlled by the PC interface card in the CMM controller. The card handles communications and condition signals between the head and the CMM controller. The PC interface card does not handle probing system signals.

The interface card receives its electrical supply from the PC's 5 V internal power supply. The PHS1 head receives its power from the PC's internal 12 V supply and an external 24 V supply.

Kinematic mount

PHS1 kinematic mounts - KM1 and KM2

A kinematic mount (KM1 or KM2) allows quick fixing of the head to the machine and a fast changeover to a PH10 PLUS system (utilising a PHA1 or PHA2).

KM1 features through quill cabling.

KM2 allows for cabling to run outside the CMM quill.

ACR2 autochange rack

ACR2 port pair

The ACR2 autochange system is an arm-changing system for the PHS1 servo positioning head system. It allows probe extensions or probe adapter arms to be exchanged to suit the probing task required.

Arms are locked or unlocked from the head by motion of the machine itself. The head engages a rack port and the machine drives the port up to unlock an arm or down to lock it in position.

No power connections or signal connectors are necessary to the rack, making installation very simple.

The ACR2 is supplied as pairs of rack ports which are mounted onto a suitable fixture supplied by the OEM. The system is modular and any number of port pairs can be used anywhere on the CMM.

Extended warranty

For peace of mind a 3-year warranty is available for your new CMM products during the first 3 months from purchase. Contact your vendor.


  • PHS1 5 axis blended moves

    The motion of the PHS1 servo positioning head can be synchronised with the movement of the CMM to form 5 axis blended moves for precise control of the stylus tip.