General wiring standards for the installation of
the SPA3-2
To achieve reliable operation of the SPA3-2, the following should be observed:
The system must be portable appliance tested (PAT) before the equipment is powered
All signal cables must be screened and all cable screens should be connected electrically to the cable connector's metal shells
It is recommended that screens for motor cables should be connected to the shell on the SPA3-2 end and connected to the motor housing
at the CMM end
Signal cables such as tacho and scale cables should be connected to the SPA3-2 and have a cable shield that runs to the machine but left
unconnected at the machine
All cable connectors should be secured to the SPA3-2 by the connector jack screws
SPA3-2 has a maximum output voltage of 80 Vdc and peak current of 9.5 A per axis. The actual peak current will be dependent on the size
of the motor fitted and the machine performance specification, therefore the cable size needs to be calculated by the system installer or
OEM.
WARNING:
The installation should only be performed by Renishaw or a Renishaw certified installation engineer.
WARNING:
Hazardous voltage warning labels must be fitted to motors where hazardous voltages are present.
CAUTION:
Motor cables must have a minimum cross section of 0.3 mm².
For SPA3‐2 supply voltage of over 60 V, motor cables must have a minimum cross section of 0.75 mm² as specified in BS EN
60204-1:2018 para. 12.2 (or current version) and have insulation rated to at least 150 V to provide adequate protection against
electric shock.
The actual peak current will be dependent on the size of the motor fitted and the machine performance specification, therefore the
cable size needs to be calculated by the system installer or OEM.
SPA3-2 installation guide
www.renishaw.com
Issued 08 2020
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