Reference Mark Set-Up; Limit Switch; Output Signals - Renishaw RGH22 Installation Manual

Reference mark set-up

To ensure unidirectional repeatability, the reference mark requires phasing with the scale in the direction
of normal datuming operation.
A reference pulse is output in both directions, but repeatability is guaranteed only in the phased direction.
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 RGH22 Data sheet (Part number L-9517-9676).
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.
If it flashes orange or goes blank, the reference mark adjuster screw should be turned anti-clockwise
1
by turn and the procedure repeated until a red flash is obtained.
8
LED flash during reference mark traverse only
Red Orange Blank

Limit switch

Limit switch detection is entirely independent of other readhead functions - the signal is only output
when the readhead is positioned over the limit switch actuator.
RGH22 RGS20 installation guide

Output signals

RGH22 D, X, Z, Y, H, P, Q, R, S, RS422A digital
Function
Power
Incremental signals
Reference mark
Limit switch
Alarm
External set-up
Shield
1
turn
8
*
NOTE: Dual limit versions (P, Q, R, S and H) utilise the black wire (pin 11) as the P limit output.
The 'E' alarm signal on these versions is only available at the orange wire as a single-ended E- output.
Dual limit readheads are only available with F, D, or X terminations.
Alarm
For RGH22D, X, Z, P, Q, R, - alarm asserted when signal amplitude <15%.
For RGH22Y, S, H - alarm asserted when: - Signal amplitude >150% - Readhead exceeds specified maximum speed
Also, outputs are 3-stated at signal amplitude <15%
15 pin D type plug (termination code D)
In-line connector plug (termination code X)
Signal Colour
Brown
5 V
Brown (link)
White
0 V
White (link)
+ Green
A
- Yellow
+ Blue
B
- Red
+ Violet
Z
- Grey
*
Q Pink
+ Black
E
- Orange
X Clear
Inner Green / Yellow
Outer –
52 16
40
66 17
15 way D-type 16 way in-line
12 way circular
plug connector
(R)
(D) (X)
7 2 A
8 12 M
2 10 B
9 11 N
14 5 G
6 6 D
13 8 R
5 1 F
12 3 K
4 4 O
10 – H
11 9 I
3 7 P
1 – E
15 11 (link) L
Case Case Case
28
52
12 pin circular plug (termination code R)
7