RGH34 series readhead - Renishaw resource centre

Installation guide
M-9537-0194-04-B
RGH34 series readhead
RGH34 Installation drawing
Dimensions and tolerances in mm.
Arrow indicates forward direction of
readhead relative to scale
(Yaw tol. ±1°)
0.20
(Roll tol. ± 1°)
A
B
0.20
B
Datum ‘A’ is the
axis of the machine
Centreline defined
by Ø12 and 90° vee
15
10.5
RGS40-S
scale shown
1.5
2.55
RGS40-S
scale shown
Optical
centreline
FPC cable
7.5
4
7.5
6
15
5.5
Ø
1.6
12.01
11.95
2
2.1
7
4.6
Optional magnetic
reference or limit
switch sensor
10.5 ± 0.3
3 min. scale width
symmetrical about
optical centreline
10
Component area
14
Limit actuator A-9531-0251
lower edge to be positioned
2.8 ± 0.5 above substrate
0.8 ± 0.5
Component area
(Pitch tol. ± 1°)
0.20
FPC cable
B
7.1
Scale surface
*From scale surface
1.5 ± 0.15*
3.9 Max. depth of
clamping surface
Reference
actuator
A-9531-0250
Readhead mounting/installation
FPC cable insertion
Mounting brackets
The RGH34 is designed to be integrated into OEM products, and as such the recommendations
given here for mounting brackets are intended only as a guide.
The FPC cable connectors on the RGH34 readhead and RGI34 interface are of the
ZIF (zero insertion force) type.
It is recommended that the cylindrical body
of the RGH34 be located by a stepped bore
(diameter 12.10 mm ± 0.05 mm) and that
it is fixed in place by means of a clamping
mechanism (as shown), or affixed by a
suitable adhesive. Care should be taken to
ensure that an even pressure is applied to
the cylindrical body to prevent distortion of
the optics.
Prior to insertion, the clip (indicated) on the connector should be pulled to the open position.
The cable can then be inserted, connections uppermost, into the connector body.
The clip should then be pushed to the closed position, securing the cable in place.
Clip in open position
Cable connections
An alternative arrangement is to mount the
readhead in a through-hole bracket, whilst
using a 1.5 mm shim to maintain ride height
tolerance. Again, the body can be secured
by a clamping mechanism or by a suitable
adhesive.
Clip in closed position
For readheads that incorporate reference mark or limit switch detection, the bracket should be
designed to allow clearance for the magnetic reference/limit sensor and actuator. A V-shaped groove
in the cylindrical body is provided as an aid to yaw alignment (see installation drawing).
NOTE: There are three ‘GAIN’ levels available for RGH34 readheads. Type A for Renishaw
RGS40-S gold tape scale, type G for Renishaw RGS40-G chrome on glass scale and type R
for RESR rings. Ensure that you are using the correct readhead for your choice of scale.
Readhead set-up
Reference mark set-up
When mounting the readhead, ensure that the scale, readhead optical window and mounting
surfaces are clean and free from obstructions.
To ensure unidirectional repeatability, the reference mark requires phasing with the scale in the
direction of normal datuming operation.
NOTE: Refer to ‘Maintenance and cleaning’ section of this manual for cleaning instructions.
A reference pulse is output in both directions, but repeatability is guaranteed only in the
phased direction.
Adjusting set-up
Once the readhead is positioned, the rideheight, pitch, yaw and roll of the unit may need to be
adjusted to achieve optimum signal strength. It should be noted that the readhead and interface must
be properly connected to the power supply to enable the set-up LED to be used.
Confirming set-up
For reliable operation, the LED should be GREEN when the readhead is moved slowly (<1 m/s)
along the full axis travel.
NOTE: The set-up LED will not indicate an optimised set-up over the reference mark.
For further details, refer also to ‘Reference mark set-up’.
The readhead should be set up correctly ensuring a green LED indication over the full length of
travel. The reference mark actuator should be installed as shown on the installation drawing.
NOTE: It is recommended that a datum procedure is performed as part of any power-up sequence
to ensure the correct datum position is recorded.
NOTE: Reference mark output is synchronised with the incremental channels, giving unit of
resolution pulse width. For further details see RGH34 Data sheet (Part number L-9517-0185).
Note: Check that the reference mark sensing option has been specified on the RGH34
and RGI34 that you have purchased.
Phasing procedure
The readhead must be moved over the reference
mark in the direction to be used for the datuming
operation. The reference mark is phased
correctly when the set-up LED flashes
Red for 0.25 seconds.
The set-up LED will exhibit one of three colours during normal use;
Green Orange Red
1
Set-up tolerances
Yaw
0° ±1°
Roll
0° ±1°
turn
If the set-up LED
flashes orange or goes
blank, the reference mark
adjuster screw should be
turned anti-clockwise by
1
8 turn and the procedure
repeated until a red flash is
obtained.
Pitch
0° ±1°
Rideheight
1.5 mm ±0.15 mm
8
LED flash during reference
mark traverse only
Red Orange Blank
Phasing procedure (continued)
RGI34 Installation drawing
Note:
1) If the readhead mounting is disturbed at any time, the reference mark will have to
be re-phased.
Dimensions and tolerances in mm.
2) A reference pulse is output in both directions, but because the reference mark can only
be phased for one direction of traverse, any indication from the LED when the readhead
is moved in the reverse direction is to be ignored.
Bracket omitted
from this view
35
8.5
3) LED flash duration is a constant 0.25 seconds, regardless of traverse speed.
12
4) LED repeater (external LED driver) signals will mimic the on-board LED apart from the
‘blank’ condition.
5) The repeater LED will go blank when the incremental output is in error (3-state).
8
Limit switch
Ground connection to case for
optimum EMC performance
(hole dia. 1 mm)
25.5
A limit switch signal is output when the readhead sensor passes the magnetic actuator.
For full output specification refer to RGH34 Data sheet (Part number L-9517-0185).
CAUTION: The limit switch feature must never be used as a fail-safe stop device.
Note: Check that the limit switch sensing option has been specified on the RGH34
and RGI34 that you have purchased.
36.5
FPC cable to RGH34 readhead.
Available in 50, 100 and
150 mm lengths
2
A pulse is output from the readhead for the duration of the passing of the magnetic actuator.
The limit switch provides an end of travel indication, repeatable to <0.1 mm (typical).
9
Recommended signal terminations
Digital outputs - type RGI34T, D, G, X, N, W, Y
30
Component area
Mounting bracket
(M-9537-0193)
supplied with interface
Customer
electronics
Interface
A B Z Q+
12
9.6
20.5
2
Cable Z0 = 120R
120R
2
7
A B Z Q*Maximum extension cable length
RGH34B -100 m, RGH34T, D, G, X, - 50 m, RGH34N, W, Y, - 20 m
27
20.5
14
2
2
2
2
2
Analogue outputs - type RGI34B
V0 V1 V2 +
4.75
12.5
Ø3.5 mounting holes 2 off
Set-up LED
120R
V0 V1 V2 -
Ø3.5 alternative
mounting holes 2 off
Electrical connection
General operating specifications
Grounding and shielding
Power supply
Double-shielded extension cable
Outer shield
Output
signals
Conductive
shield
5 V ± 5% Ripple operating non-operating operating Readhead: Interface: Inner shield
FPC Cable
0V
Acceleration
Conductive
mounting plate
RGH34
readhead
Interface ‘case’
connected to
ground
Case
Shock
Vibration
Mass
For optimum performance, ensure 100% screening
120 mA
NOTE: Current consumption figures refer to
unterminated interfaces .
For digital outputs a further 25 mA per channel pair
(eg A+, A-) will be drawn when terminated with 120 Ω.
For analogue outputs a further 20 mA will be drawn
when terminated with 120 Ω.
Renishaw encoder systems must be powered from a
5 V dc supply complying with the requirements for
SELV of standard EN (IEC) 60950.
200 mVpp maximum@ frequency up to 500 kHz maximum.
300 m/s2 BS EN 60068-2-7:1993
(IEC 68-2-7:1983)
1000 m/s2, 11 ms, 1/2 sine BS EN 60068-2-27:1993
(IEC 68-2-27:1987)
100 m/s2, 55 to 2000 Hz BS EN 60068-2-6:1996
(IEC 68-2-6:1995)
2g
3g
– Ground the readhead mounting bracket
NOTE: Class 1M LED product. LED radiation. Do not view directly with optical instruments.
– Ensure continuity of all shields
Maximum speed
– Use double shielded extension cable
– Connect interface CASE to ground
– Use shielded connector shells on all cable connections
The table below shows the maximum speed and associated minimum recommended counter clock
frequency for all digital output interfaces. The RGI34N, W and Y options have clocked outputs. These
are designed to prevent fine edge separations being missed by receiving electronics utilising slower
clock speeds.
– Terminate the inner shield to 0V power at the customer interface
– Maximise the distance between encoder and motor cables
FPC cables
FPC (flexible printed circuit) cables should be ordered separately from your local Renishaw
representative. The part numbers for the standard lengths are listed below.
Part
Part number
50 mm FPC
A-9537-0182
100 mm FPC
150 mm FPC
Maximum speed (m/s)
Head type
RGS40-S
RGS40-G+RESR
-3dB
6
4.5
-6dB
8
5.5
Minimum recommended
counter clock frequency (MHz)
–
Analogue
B (1Vpp)
Digital
T (10 µm)
8
5.5
D (5 µm)
8
5
Encoder velocity (m/s)
G (2 µm)
7.5
4
Resolution (µm)
X (1 µm)
6
3
x4
safety
factor
Maximum speed (m/s)-all scale types
N
(0.4 µm)
W
(0.2 µm)
A-9537-0183
N (0.4 µm)
W (0.2 µm)
Y (0.1 µm)
Option code
A-9537-0184
30
–
31
–
32
33
Y
(0.1 µm)
N
(0.4 µm)
W
(0.2 µm)
Y
(0.1 µm)
1.3
0.6
–
12
12
0.9
0.45
–
8
8
1.3
–
–
6
–
–
0.9
0.45
0.2
4
4
4
€
Pin out diagram
Readhead part numbers
RGI34 digital RS422A output types T, D, G, X, N, W, Y and
RGI34 analogue 1Vpp output type B
RGH34U
FPC connector
00A
00A
Datum
9
00A - standard reference sensor
00B - limit switch sensor (not available with scale type 02R)
00C - no sensor
10
Scale type
00A - Renishaw RGS40-S gold scale
02G - Renishaw RGS40-G glass scale
02R - Renishaw RESR angle encoder ring
1
Signal
output
Readhead series
10
NOTE: Not all combinations are valid. Check valid combinations and all available options online at www.renishaw.com/epc
1
2
Interface part numbers
RGI34
Signal
0V
FPC
connector
pin
1, 2
A phase
3
B phase
4
C phase
5
V mid
6
Hall
7
5V
8, 9, 10
Digital
Output
signal
Through
hole
5V
9
0V
A+
signals
Reference
mark (Z) or
Limit switch
(Q) (if fitted)
External
LED driver
A
00
5V
9
10
0V
10
8
V 1+
8
Datum
V1-
7
A - standard reference sensor (choose A also if no sensor
was chosen when configuring the RGH34U readhead)
B - limit switch sensor (RGI34D, G, N, T, W, X, and Y only)
V 2+
6
V2-
5
V 0+
2
V0-
1
Analogue
Power
A-
00
Through
hole
Power
Incremental
B
Output
signal
7
B+
2
B-
1
Z-/Q+
6
Z+/Q-
5
Red
4
Green
3
Incremental
signals
Reference
mark
(if fitted)
Clocked output
00 - not clocked (RGI34B, D, G, T and X only)
30 - 12 MHz customer clock (RGI34W and Y only)
31 - 8 MHz customer clock (RGI34W and Y only)
32 - 6 MHz customer clock (RGI34N only)
33 - 4 MHz customer clock (RGI34N, W, and Y only)
Option
00 - FPC
Output
Analogue
Digital
B - 1Vpp
T - 10 µm
D - 5 µm
G - 2 µm
X - 1 µm
N - 0.4 µm
W - 0.2 µm
Y - 0.1 µm
Interface series
NOTE: RGH34 readhead requires an RGI34 interface to function as a complete system.
NOTE: Not all combinations are valid. Check valid combinations and all available options online at www.renishaw.com/epc
Electrical Integration
Storage and handling (continued)
The RGH34 and RGI34 have been designed as system components and are compliant with EMC
regulations for products of their type. Care must be taken with shielding and grounding arrangements
to ensure EMC performance once installed. It is the system integrator’s responsibility to implement, test
and prove EMC compatibility for the whole machine.
Patents
Features of Renishaw’s encoder systems and similar products are the subjects of the following
patents and patent applications:
EP 0274491
EP 0383901
JP 248,895/1993
EP 826138 B
JP 2003-512,611
US 4,974,962
JP 2,963,926
US 5,302,820
JP 3,676,819
US 6,588,333 B1
EP 0274492
US 5,088,209
EP 0748436
US 6,051,971
US 4926566
EP 0543513
US 5,861,953
EP 1147377
N-heptane
CH3(CH2)5CH3
Acetone
CH3COCH3
Chlorinated
Solvents
Further information
For further information relating to the installation of RGH34 readheads, see also the RGH34 Data sheet
(Part number L-9517-0185), and the Scale installation guide (Part number M-9517-2855). These can
be downloaded from our website www.renishaw.com/encoder and are also available from your local
representative.
This document may not be copied or reproduced in whole or in part, or transferred to any other media
or language, by any means without the written prior permission of Renishaw.
The publication of material within this document does not imply freedom from the patent rights of
Renishaw plc.
Propan-2-ol
Methylated
Spirits
CH3CHOHCH3
Disclaimer
RENISHAW HAS MADE CONSIDERABLE EFFORTS TO ENSURE THE CONTENT OF THIS
DOCUMENT IS CORRECT AT THE DATE OF PUBLICATION BUT MAKES NO WARRANTIES
OR REPRESENTATIONS REGARDING THE CONTENT. RENISHAW EXCLUDES LIABILITY,
HOWSOEVER ARISING, FOR ANY INACCURACIES IN THIS DOCUMENT.
Storage and handling
+70 °C
-20 °C
+55 °C
0 °C
Storage <95% RH
Operating <80% RH
Renishaw plc
New Mills, Wotton-under-Edge,
Gloucestershire, GL12 8JR
United Kingdom
T +44 (0)1453 524524
F +44 (0)1453 524901
E [email protected]
www.renishaw.com
For worldwide contact details,
please visit our main website at
www.renishaw.com/contact
RENISHAW® and the probe emblem used in the RENISHAW logo are
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Renishaw reserves the right to change specifications without notice.
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All rights reserved
Issued 0309
*M-9537-0194-04*