Renishaw OMI-2 User manual

Installation and user’s guide
H-2000-5233-03-A
OMI-2 - optical machine interface

© 2005–2009 Renishaw plc.All rights reserved.
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 prior written
permission of Renishaw.
The publication of material within this document
does not imply freedom from the patent rights of
Renishaw plc.
Disclaimer
RENISHAW HAS MADE CONSIDERABLE EFFORTS
TO ENSURE THE CONTENT OF THIS DOCUMENT
IS CORRECT ATTHE DATE OF PUBLICATION BUT
MAKES NO WARRANTIES OR REPRESENTATIONS
REGARDING THE CONTENT. RENISHAW
EXCLUDES LIABILITY, HOWSOEVER ARISING,
FOR ANY INACCURACIES IN THIS DOCUMENT.
Renishaw part no: H-2000-5233-03-A
Issued: 04.09
Trademarks
RENISHAW® and the probe emblem used in the
RENISHAW logo are registered trademarks of
Renishaw plc in the UK and other countries.
apply innovation is a trademark of Renishaw plc.
All other brand names and product names used
in this document are trade names, service marks,
trademarks, or registered trademarks of their
respective owners.

1Contents
Contents
EC declaration of conformity ................2
FCC declaration (USA) . . . . . . . . . . . . . . . . . . . .3
Safety .................................3
Introduction.............................5
Mounting bracket.........................6
OMI-2 visual diagnostics ...................7
OMI-2outputs...........................9
OMI-2 output waveforms ..................12
Switches SW1, SW2 and start input . . . . . . . . .14
Switch SW1 output configuration............14
Switch SW2 output configuration............15
Wiring diagram .........................16
Installation with inspection and tool setting
probe .................................17
Remote external audible output.............17
OMI-2 cable............................18
OMI-2 cable sealing . . . . . . . . . . . . . . . . . . . . .18
Fitting flexible conduit . . . . . . . . . . . . . . . . . . . .19
Removing the OMI-2 window . . . . . . . . . . . . . .20
Removing the OMI-2 label.................21
Refitting the OMI-2 label . . . . . . . . . . . . . . . . . .21
Changing the reception range..............22
Fitting the OMI-2 window..................23
Screwtorquevalues.....................24
Fault-finding............................25
Parts list...............................29

2
EC DECLARATION OF CONFORMITY
Renishaw plc declares that the product:
Name: OMI-2
Description: Optical machine interface
has been manufactured in conformity with the following standard:
BS EN 61326-1:2006 Electrical equipment for measurement, control and laboratory use – EMC
requirements.
Immunity to table 2 – industrial locations.
Emissions to class A – industrial locations.
BS EN 60825-12:2004 Safety of laser products - Part 12: Safety of free space optical communication
systems used for transmission of information.
and that it complies with the requirements of directives:
2004/108/EC Electromagnetic compatibility
2006/95/EC Low voltage
The above information is summarised from the full EC declaration of conformity. A copy is available
from Renishaw on request.
c

3
FCC DECLARATION (USA)
FCC Section 15.19
This device complies with Part 15 of the FCC rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device may accept any interference
received, including interference that may cause
undesired operation.
FCC Section 15.105
This equipment has been tested and found to
comply with the limits for a Class A digital device,
pursuant to Part 15 of the FCC rules.These limits
are designed to provide reasonable protection
against harmful interference when the equipment is
operated in a commercial environment.
This equipment generates, uses, and can radiate
radio frequency energy and, if not installed and
used in accordance with the instruction manual, may
cause harmful interference to radio communications.
Operation of this equipment in a residential area is
likely to cause harmful interference, in which case
you will be required to correct the interference at
your own expense.
FCC Section 15.21
The user is cautioned that any changes or
modifications not expressly approved by Renishaw
plc or authorised representative could void the user’s
authority to operate the equipment.
SAFETY
Information for the user
Beware of unexpected movement.The user should
remain outside of the full working envelope of probe
head/extension/probe combinations.
Handle and dispose of batteries in accordance with
the manufacturer’s recommendations. Use only the
recommended batteries. Do not allow the battery
terminals to contact other metallic objects.
In all applications involving the use of machine tools
or CMMs, eye protection is recommended.
Refer to the machine supplier’s operating
instructions.
Information for the machine supplier
It is the machine supplier’s responsibility to ensure
that the user is made aware of any hazards involved
in operation, including those mentioned in Renishaw
product documentation, and to ensure that adequate
guards and safety interlocks are provided.
Under certain circumstances the probe signal may
falsely indicate a probe seated condition.Do not rely
on probe signals to stop the machine’s movement.

4
Warranty
Equipment requiring attention under warranty
must be returned to your supplier. No claims will
be considered where Renishaw equipment has
been misused, or repairs or adjustments have
been attempted by unauthorised persons.
Care of the OMI-2
Keep system components clean and treat the
OMI-2 with care.
Do not apply labels to the front of the OMI-2.
Changes to equipment
Renishaw reserves the right to change
specifications without obligation to change
equipment previously sold.
Weight
OMI-2 including 8 metres (26 ft) of cable =
1000 g (35 oz).
OMI-2 including 15 metres (49 ft) of cable =
1500 g (53 oz).
Sealing
The unit is fully sealed to IPX8.
CNC machine
CNC machine tools must always be operated
by competent persons in accordance with
manufacturer’s instructions.
Temperature
The OMI-2 is specified for storage over –10 °C to
70° C (14 °F to 158° F) and operation over 0 °C
to 60 °C (32 °F to 140 °F) ambient temperature
range.
Patent notice
Features of products shown in this guide, and of
related products, are the subject of the following
patents and/or patent applications:
EP 0974208 US 6,839,563 B1
EP 1503524 B

5
Introduction
OMI-2
The OMI-2 is a combined optical receiver and
machine interface that is designed to be mounted
within the machine’s working envelope.
The OMI-2 operates using a‘Modulated’optical
transmission mode and is compatible with machine
probes that also operate in‘Modulated’mode.
Power supply
The OMI-2 can draw its supply from the CNC
machine’s 12 Vdc to 30Vdc supply. Alternatively,
power may be supplied from a Renishaw PSU3
power supply unit.The maximum supply current
is 40 mA and the maximum current is 200 mA
during a START signal.
CAUTION: This equipment will only
perform to specification if the power supply 0V is
connected to the machine ground (star point).
!
40 (1.57)
84 (3.30)
40 (1.57)
40 (1.57)
46.7 (1.84)
45 (1.77)
63 (2.48)
16 (0.63)
dimensions mm (in)
Contact Renishaw for cable rear exit version
Input voltage ripple
The input voltage ripple must not cause the
voltage to fall below 12 V or rise above 30 V.
Introduction

6Mounting bracket
Mounting bracket (optional) dimensions mm (in)
3 holes Ø6.4 (0.25)
25
(0.98) 25
(0.98)
19 (0.75)
38 (1.50)
45
(1.77) 25
(0.98) 30
(1.18)
3 grip protrusions
100.5 (3.95)
90 (3.54)
2.0
(0.08)
2.0
(0.08) 3 pairs of holes Ø5.3 (0.20) permit OMI-2
mounting in alternative orientation
45 (1.77) 45°
NOTE:
Install the OMI-2 with the cable
exiting from the lower side for
good coolant run-off.
The mounting bracket cannot
be used with an OMI-2 in rear
exit configuration.

7
OMI-2 visual diagnostics
OMI-2 visual diagnostics
A visual indication of system status is provided
by LEDs. Indication is provided for START,
LOW BATTERY, PROBE STATUS, ERROR and
SIGNAL CONDITION.
1. LED (yellow) – START signal status
Lit when a START signal is transmitted to
the probe.
This LED will either flash once when
a machine-controlled START signal is
commanded, or flash at one second
intervals when the system is set to ‘Auto-
Start’mode and is waiting for a probe
transmission signal.
2. LED (red) – LOW BATTERY
When the OMP battery voltage falls below
a set level, the low battery output device
changes state and causes the LOW
BATTERY LED to be lit.
Replace the OMP battery as soon as
practicable after the LED is lit.
KEEPTHE
WINDOW CLEAN
1 2 3 4 5
Magnetic label
A summary of OMI-2 LED activity is provided on
a magnetic label.The label may be placed on any
machine flat metal surface.

8 OMI-2 visual diagnostics
3. LED (green, red) – PROBE STATUS
This bi-colour LED is lit when the OMI-2 is
powered.
Green – Probe is seated.
Red – Probe is triggered or an error has
occurred.
The change of colour of this LED will
coincide with the probe status output
device’s changing state.
4. LED (red, blue, yellow, violet) – ERROR
Indicates transmission error condition, e.g.
optical beam obstructed/probe out of optical
range/probe switched off/battery dead.
Red – The signal from the probe has
either failed or stopped.
Blue – A second modulated signal is
being received.
Yellow – Interference or a weak probe
signal is being received.
Violet – Interference or a weak probe
signal has caused the trigger
instant to be delayed.
NOTE: If the ERROR SSR is activated
because the blue or yellow condition causes
the loss of a good probe signal, or the violet
condition occurs, then the indication persists
until the Machine Start is activated or one
hour has elapsed.
5. LED (red, yellow, green) – Infrared
SIGNAL CONDITION received from probe
As long as there is power to the system, this
LED will always be lit. It is a tri-colour LED
and indicates as follows:
Red – There is no signal from the
probe.
Yellow – Either the signal received from
probe is too weak or interference
is present.
Green – The condition of the signal
received from the probe is good.

9OMI-2 outputs
OMI-2 outputs
There are five outputs:
Probe status 1 (SSR)
Probe status 2a (5 V isolated driven skip)
Probe status 2b (driven at power supply
voltage)
Error (SSR)
Low battery (SSR)
All outputs can be inverted by using switches
SW1 and SW2 – see page 14.
Probe status 1, Error, Low battery (SSR)
‘On’resistance = 50 ohms max.
Load voltage = 40 V max.
Load current = 100 mA max.
Switching times
Open to closed = 100 µs max.
Closed to open = 25 µs max.
Probe status 2a (5V isolated driven skip)
Load current = 50 mA max.
Output voltages
Sourcing = 4.5V min at 10 mA.
= 2.4V min at 50 mA.
Sinking = 0.4V max at 10 mA.
= 1.3V max at 50 mA.
Switching times
Low to high = 20 µs max.
High to low = 10 µs max.

10 OMI-2 outputs
Probe status 2b (driven at power supply
voltage)
Load current = 50 mA max.
Output voltages
Sourcing (voltage supply – output voltage)
= 2.6V max at 10 mA.
= 3.5V max at 50 mA.
Sinking = 2.0V max at 10 mA.
= 2.9V max at 50 mA.
Switching times
Low to high = 10 µs max.
High to low = 10 µs max.
The Low Battery, Probe Status, and Error LEDs
will start flashing red when an output overload
has occurred. All outputs will be switched off. If
this occurs, turn off the power supply and remove
the source of the problem.Turning on the power
supply will reset the OMI-2.

11OMI-2 outputs
CAUTION:
Power supply voltage
Do not exceed 30V between the black wire and
the screen wire (green/yellow), or the red wire
and the screen wire (green/yellow), or the red
and black wires (power supply), as this could
result in permanent damage to the OMI-2 and/or
the customer’s power supply.
The use of in-line fuses at the machine cabinet
end is recommended to provide protection for the
OMI-2 and cable.
Screen connection
A good connection should be made to machine
ground (star point).
Output
Ensure that outputs from the OMI-2 do not
exceed specified current ratings.
!

12 OMI-2 output waveforms
OMI-2 output waveforms
Probe
switch
on
Seated
Power
off
Probe
trigger
Triggered
Probe
reseat
Seated Error
e.g. low
signal Error
clear
SSR closed
Normally open
Probe
switch
off
Low
battery
PROBE
PROBE
STATUS1
(LEVEL)
OMI-2
SSR/driven
outputs
Normally open
PROBE
STATUS 1
(PULSED)
Normally
closed
ERROR
Outputs can be inverted by switches – see
page 14.
SSR open
SSR open
SSR open
SSR closed
SSR closed

13OMI-2 output waveforms
Normally open
PROBE
LOW
BATTERY
OMI-2
SSR/driven
outputs
Normally low
PROBE
STATUS 2a/2b
(LEVEL)
Normally low
PROBE
STATUS 2a/2b
(PULSED)
Probe
switch
on
Seated
Power
off
Probe
trigger
Triggered
Probe
reseat
Seated Error
e.g. low
signal Error
clear
Probe
switch
off
Low
battery
SSR open
Output high
Output high
SSR closed
Output low
Output low
SIGNAL DELAYS
1. Transmission delay. Probe trigger to output
change of state = 1.3 ms max.
2. Start delay.Time from initiation of start signal
to valid signal transmission = 410 ms max.
NOTE: Pulsed outputs are 40 ms ±1 ms duration.

14 Switches SW1, SW2 and start input
To gain access to the switches,
remove the OMI-2 window
Switches SW1, SW2 and start
input
N/C
ON
LOW
BATTERY
N/C
Pulsed N/O
Level
ERROR
N/C
PROBE
STATUS 1
SW1 SW2
N/O = Normally Open
N/C = Normally Closed
Switch SW1 output configuration
Factory settings shown are for:
A-5191-0049
A-5191-0050
CAUTION: Exercise caution when using
error SSR in N/O mode, as a wiring fault could
cause loss of error condition and therefore could
result in a non-fail safe condition.
!
CAUTION: Only qualified persons should
adjust switches.
!
N/O N/O

15Switch SW2 output configuration
MACHINE
START
Pulsed Normally
high
Pulsed
Normally
low
START START
RANGE
100%
ON
Machine
PROBE STATUS
2a/2b
Level
Auto start
‘Auto start’ selection causes the system to send
a START signal at one second intervals, and
should only be used when there is no available
output from the machine control. In this mode,
ensure start signals cannot be received by
probes in the tool changer or on other machines.
Machine start
‘Machine start’is configurable as a level or pulsed
signal.
Level 10 V – 30 V (2.4 mA at 24 V)
When input is active, the probe is
switched on.
Pulsed 12 V – 30 V (10 mA at 24V)
The probe toggles from being
switched on/off.The minimum
pulse width is 10 ms.
Machine start wires
White = positive
Brown = negative
Switch SW2 output configuration
Factory settings shown are for:
A-5191-0049
A-5191-0050
Level Auto 50%

16 Wiring diagram
CAUTION: The power supply 0 V should be
terminated at the machine ground (star point). If a negative
supply is used, then the negative output must be fused.
Wiring diagram (with the output groupings shown)
12 V to 30 V
Turquoise
Turquoise/black
Violet
Violet/black
Green
Green/black
White
Brown
Screen
OMI-2
5 V Driver
Driver
Yellow
Grey
Orange
Red
Black
Green/yellow Machine ground (star point)
Power supply (12 V to 30 V)
Probe status 1 (SSR)
Low battery (SSR)
Error (SSR)
Machine start input
Probe status 2a
(5 V isolated driven skip)
+ve
–ve
Signal
Return
Probe status 2b (driven at power supply voltage)
!
0 V

17Inspection and tool setting probe/Remote external audible output
Installation with inspection and
tool setting probe
On machines where the OMI-2 is to be integrated
with a tool setting probe input, and only one
probe input is provided on the control, an M code
can be utilised to drive an external relay that will
select which probe is monitored.
Remote external audible output
Any one of the probe status outputs can be used
to drive an external audible indicator when set to
pulsed – see section “OMI-2 outputs”.
NOTE: Audible indicator operation is not
possible if both skip drives are being monitored
by the control.
CONTROL
PROBE INPUT
M CODE
Probe status from OMI-2
Probe status from tool setter
RELAY

18 OMI-2 cable/OMI-2 cable sealing
OMI-2 cable
Cable termination
A ferrule should be crimped onto each cable wire
for more positive connection at the terminal box.
Standard cable variants
The OMI-2 standard polyurethane cables are 8 m
(26 ft) and 15 m (49 ft) long.
Contact Renishaw for other cable lengths.
Cable specification
Ø7.5 mm (0.29 in), 13 core screened cable, each
core 18 x 0.1 mm.
NOTE: The maximum length of the specified
cable must not exceed 25 m (82 ft).
OMI-2 cable sealing
Coolant and dirt are prevented from entering the
OMI-2 by the cable sealing gland.The OMI-2
cable can be protected against physical damage
by fitting flexible conduit if required.
Recommended flexible conduit is AnametTM
Sealtite HFX (5/16 in) polyurethane.A conduit kit
is available – see Parts list.
CAUTION: Failure to adequately protect
the cable can result in system failure due to either
cable damage or coolant ingress through cores
into the OMI-2.
Failure due to inadequate cable protection will
invalidate the warranty.
When tightening or loosening nut Bonto the
conduit, ensure that torque is only applied
between Aand B.
!