General Specifications; Scale Specifications - Renishaw RGH24 Installation Manual

General specifications

Power supply 5 V ± 5% 120 mA
NOTE: Current consumption figures refer to unterminated readheads.
For digital outputs a further 25 mA per channel pair (e.g. A+, A-)
will be drawn when terminated with 120R.
For analogue outputs a further 20 mA will be drawn when
terminated with 120R.
Power from a 5 V dc supply complying with the requirements for
SELV of standard IEC BS EN 60950-1.
Ripple 200 mVpp@frequency up to 500 kHz maximum.
Temperature Storage -20 °C to +70 °C
Operating 0 °C to +55 °C
Humidity
95% relative humidity (non condensing) to EN 60068-2-78
Sealing
IP40
Acceleration
Operating 500 m/s², 3 axes
Shock Non-operating 1000 m/s², 6 ms, ½ sine, 3 axes
Vibration Operating 100 m/s² max @ 55 Hz to 2000 Hz, 3 axes
Mass Readhead 11 g
Cable
Cable 8 core, double shield, maximum diameter 4.4 mm.
Flex life >20 x 10
The RGH24 series readheads have been designed to the relevant EMC standards, but must be
correctly integrated to achieve EMC compliance. In particular, attention to shielding arrangements
is critical. Renishaw recommends the use of a double screened cable to connect RGH24 JST as
used in the cable variants of the RGH24.
RGH24 RGS20 installation guide
34 g/m
cycles at 20 mm bend radius.
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Scale specifications

Scale type RGS20-S - reflective gold plated steel tape with protective lacquer coating.
Adhesive backing tape allows direct mounting to the machine substrate.
RGS20-P - reflective gold plated steel tape with tough polyester coating
for applications using harsh solvents. Adhesive backing tape allows direct
mounting to the machine substrate.
Scale period RGS20-S, RGS20-P = 20 μm
Linearity RGS20-S = ±3 μm /m
RGS20-P = ±5 μm /m
Scale length Up to 50 m (>50 m by special order)
Form RGS20-S = 0.2 mm x 6 mm (H x W) includes adhesive
RGS20-P = 0.3 mm x 6.3 mm (H x W) includes adhesive
Substrate materials Metals, ceramics and composites with expansion coefficients between
0 and 22 μm/m/°C
(steel, aluminium, invar, granite, ceramic etc.)
Expansion coefficient Scale expansion matches that of substrate material when scale ends are
fixed by epoxy mounted end clamps
End fixing Epoxy mounted end clamps (A-9523-4015) using 2 part epoxy adhesive
(A-9531-0342)
Scale end movement <1 μm over temperature range -20 °C to +50 °C
Temperature: -10 °C to +120 °C (Scale only)
Operating specification
Minimum installation temperature: 10 °C
Humidity: 95% relative humidity (non condensing) to EN 60068-2-78
Storage
Temperature: -20 °C to +70 °C
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