Electrical Connections; Output Specifications - Renishaw VIONiC RTLC20-S Installation Manual

Electrical connections

Grounding and shielding
VIONiC readhead
Readhead
termination/connector
Shield
IMPORTANT: The shield should be connected to the machine earth (Field Ground).
For JST variants the ferrule should be connected to machine earth.
Maximum readhead cable length: 3 m
Maximum extension cable length: Dependent on cable type, readhead cable length and clock speed.
Contact your local Renishaw representative for more information.
Recommended signal termination
0 V
Readhead
A B Z+
120R
Cable Z = 120R
0
A B Z−
0 V
Standard RS422A line receiver circuitry.
Capacitors recommended for improved noise immunity.
Single ended alarm signal termination
(Alarm signal not available with 'A' cable termination)
5 V
Customer
4k7
electronics
Readhead
1k8
100R
E−
100nF
4k7
VIONiC RTLC20-S installation guide
Customer
electronics
5 V
0 V
Limit output
(Limit output not available with
220 pF Customer
'A' cable termination)
electronics
5 V to 24 V
P Q
*
Select R so that maximum
220 pF
current does not exceed 10 mA.
Alternatively, use a suitable
relay or opto-isolator.
Remote CAL operation
CAL
0 V
Remote operation of the CAL/AGC
is possible via CAL signal.

Output specifications

Digital output signals
Form – Square wave differential line driver to EIA RS422A (except limits P and Q)
Incremental † 2 channels A and B in quadrature (90° phase shifted)
Output
Signal period P
signals
A
B
Reference
†
Z
R*
Limits Open collector output, asynchronous pulse
(Limit output not available with 'A' cable termination)
Active high
P Q
~
Length of limit actuator
Alarm
Line driven (Asynchronous pulse)
(Line driven alarm signal not available with 'A' cable termination)
E−
> 15 ms
or 3-state alarm
Differentially transmitted signals forced open circuit for > 15 ms when alarm conditions valid.
† Inverse signals not shown for clarity
Resolution S
NOTE: A wide reference mark option, outputting
a reference pulse for the duration of the signal
Synchronised pulse Z,
period is available.
duration as resolution.
Bi-directionally repeatable. Contact your local Renishaw representative for
more information.
Repeatability < 0.1 mm
Alarm asserted when:
– Signal amplitude < 20% or > 135%
– Readhead speed too high for reliable operation
Resolution P S
option code (µm) (µm)
D 20 5
X 4 1
Z
2 0.5
W 0.8 0.2
Y 0.4 0.1
H 0.2 0.05
M
0.16 0.04
P 0.1 0.025
I 0.08 0.02
O 0.04 0.01
Q
0.02 0.005
R 0.01 0.0025
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