Renishaw OMI-2H User manual

OMI-2H optical machine interface
Installation guide
H-5157-8504-01-B

Renishaw part no:
First issued:
Revised
H-5157-8504-01-B
04.2016
12.2022
© 2016–2022 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 plc.
Renishaw plc. Registered in England and Wales. Company no: 1106260. Registered office: New Mills,
Wotton-under-Edge, Gloucestershire, GL12 8JR, UK.
Compliance information for this product is available by scanning the QR code or visiting
www.renishaw.com/mtpdoc

i
Contents
Before you begin .............................................................1.1
Disclaimer .................................................................1.1
Trade marks................................................................1.1
Warranty ..................................................................1.1
CNC machines .............................................................1.1
Care of the interface .........................................................1.2
Patents ...................................................................1.2
Intended use ...............................................................1.2
Safety ....................................................................1.2
OMI-2H basics................................................................2.1
Introduction ................................................................2.1
Power supply ............................................................2.1
Input voltage ripple........................................................2.1
OMI-2H visual diagnostics.....................................................2.2
START SIGNAL LED (yellow)................................................2.3
LOW BATTERY LED (red) ..................................................2.3
PROBE STATUS LED (green, red)............................................2.3
ERROR LED (red, blue, yellow) ..............................................2.3
SIGNAL CONDITION LED (red, yellow, green) ..................................2.3
ACTIVE SYSTEM LEDs (green) .............................................2.3
OMI-2H inputs ..............................................................2.4
OMI-2H output..............................................................2.4
OMI-2H output waveform .....................................................2.5
Switch SW2................................................................2.6
Switch on / switch off ......................................................2.7
OMI-2H dimensions..........................................................2.8
OMI-2H specification.........................................................2.9

OMI-2H installation guide
ii
Contents
System installation ...........................................................3.1
Mounting bracket (optional)....................................................3.1
Wiring diagram .............................................................3.2
OMI-2H cable ..............................................................3.3
Cable sealing ............................................................3.3
Fitting flexible conduit......................................................3.4
Screw torque values Nm (lbf.ft) .................................................3.5
Maintenance .................................................................4.1
Maintenance ...............................................................4.1
Removing the OMI-2H window .................................................4.2
Fitting the OMI-2H window ....................................................4.3
Fault-finding .................................................................5.1
Parts list .....................................................................6.1

1.1
Before you begin
Disclaimer
WHILE CONSIDERABLE EFFORT WAS MADE TO VERIFY THE ACCURACY OF THIS DOCUMENT
AT PUBLICATION, ALL WARRANTIES, CONDITIONS, REPRESENTATIONS AND LIABILITY,
HOWSOEVER ARISING, ARE EXCLUDED TO THE EXTENT PERMITTED BY LAW.
RENISHAW RESERVES THE RIGHT TO MAKE CHANGES TO THIS DOCUMENT AND TO THE
EQUIPMENT, AND/OR SOFTWARE AND THE SPECIFICATION DESCRIBED HEREIN WITHOUT
OBLIGATION TO PROVIDE NOTICE OF SUCH CHANGES.
Trade marks
RENISHAW® and the probe symbol are registered trade marks of Renishaw plc. Renishaw
product names, designations and the mark ‘apply innovation’ are trade marks of Renishaw plc or its
subsidiaries.
Other brand, product or company names are trade marks of their respective owners.
Warranty
Unless you and Renishaw have agreed and signed a separate written agreement, the equipment
and/or software are sold subject to the Renishaw Standard Terms and Conditions supplied with such
equipment and/or software, or available on request from your local Renishaw office.
Renishaw warrants its equipment and software for a limited period (as set out in the Standard Terms
and Conditions), provided that they are installed and used exactly as defined in associated Renishaw
documentation. You should consult these Standard Terms and Conditions to find out the full details of
your warranty.
Equipment and/or software purchased by you from a third-party supplier is subject to separate terms
and conditions supplied with such equipment and/or software. You should contact your third-party
supplier for details.
CNC machines
CNC machine tools must always be operated by fully trained personnel in accordance with the
manufacturer's instructions.

OMI-2H installation guide
1.2
Before you begin
Care of the interface
Keep system components clean.
Patents
None applicable.
Intended use
The OMI-2H, which acts as a combined optical transceiver and machine interface, converts signals
from the optical probe into a voltage-free solid state relay (SSR) output for transmission to the CNC
machine controller.
Safety
Information to the user
In all applications involving the use of machine tools, eye protection is recommended.
The OMI-2H has a glass window. Handle with care if broken to avoid injury.
Information to the machine supplier/ installer
It is the machine supplier’s responsibility to ensure that the user is made aware of any hazards
involved during operation, including those mentioned in Renishaw product literature, and to ensure that
adequate guards and safety interlocks are provided.
If the probe system fails, the probe signal may falsely indicate a probe seated condition. Do not rely on
probe signals to halt the movement of the machine.
Information to the equipment installer
All Renishaw equipment is designed to comply with the relevant EC and FCC regulatory requirements.
It is the responsibility of the equipment installer to ensure that the following guidelines are adhered to,
in order for the product to function in accordance with these regulations:
•any interface MUST be installed in a position away from any potential sources of electrical noise,
(for example power transformers, servo drives);
•all 0V/ground connections should be connected to the machine “star point” (the “star point” is a
single point return for all equipment ground and screen cables).This is very important, and failure
to adhere to this can cause a potential difference between grounds;
•all screens must be connected as outlined in the user instructions;
•cables must not be routed alongside high-current sources, (for example motor power supply
cables), or be near high-speed data lines;
•cable lengths should always be kept to a minimum.
•the dc supply to this equipment must be derived from a source which is approved to
BSENIEC62368-1

1.3
Before you begin
Equipment operation
If this equipment is used in a manner not specified by the manufacturer, the protection provided by the
equipment may be impaired.
Optical safety
This product contains LEDs that emit both visible and invisible light.
OMI-2H is ranked Risk Group: Exempt (safe by design).
The product was evaluated and classified using the following standard:
BS EN 62471:2008 The photobiological safety of lamps and lamp systems.
Renishaw recommends that you do not stare at or look directly into any LED device, irrespective of its
risk classification.

OMI-2H installation guide
1.4
Before you begin
This page is intentionally left blank.

2.1
Introduction
The OMI-2H is a combined optical receiver and machine interface which is designed to be mounted
within the machine’s working envelope.
The OMI-2H operates using a ‘Modulated’ optical transmission mode and is compatible with machine
probes that also operate in ‘Modulated’ mode.
Power supply
The OMI-2H can draw its supply from the CNC machine’s nominal 12 Vdc to 30 Vdc supply.
The maximum peak supply current is 160 mA when the OMI-2H is transmitting. The average supply
current is 40 mA when the OMI-2H is receiving.
The values quoted are for a 24 Vdc supply and assume all outputs are open circuit.
CAUTION: This equipment will only perform to specication if the power supply 0 V is connected to
the machine ground (“star point”).
Input voltage ripple
The input voltage ripple must not cause the voltage to fall below 12 V or rise above 30 V.
OMI-2H basics

OMI-2H installation guide
2.2
OMI-2H basics
OMI-2H visual diagnostics
A visual indication of system status is provided by
LEDs. Indication is provided for:
•START;
•LOW BATTERY;
•PROBE STATUS;
•ERROR;
•SIGNAL;
•ACTIVE SYSTEM.
ERROR LED
PROBE STATUS LED
LOW BATTERY LED
SIGNAL LED
START LED
NOTE: Keep the window clean (For more information see Section 4, “Maintenance”).
ACTIVE SYSTEM
LED
ACTIVE SYSTEM
LED

2.3
OMI-2H basics
START SIGNAL LED (yellow)
This LED will ash once when a machine control START signal is commanded.
LOW BATTERY LED (red)
The LED is lit when the activated probe battery voltage falls below a set level.
Replace the probe battery as soon as is practicable after this LED is lit.
PROBE STATUS LED (green, red)
This bicolour LED is lit when the OMI-2H 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 devices changing state.
ERROR LED (red, blue, yellow)
Indicates a transmission error condition,
e.g. optical beam obstructed, probe out of optical range, probe switched off or battery dead.
Red – No transmission:
The signal from the probe has either failed or has stopped.
Blue – Multiple probe detected:
A second modulated signal is being received.
Yellow – Interference:
Interference or a weak probe signal is being received.
NOTE: The indication of a blue or yellow error condition resulting from the loss of a good probe signal
will persist until the active system input (Probe 1 or Probe 2) is deactivated.
SIGNAL CONDITION LED (red, yellow, green)
This tricolour LED is lit when the OMI-2H is powered and indicates as follows:
Red – No communication:
There is no signal from the probe.
Yellow – Interference:
Either the signal received from the probe is too weak, or interference is present.
Green – Good communication:
The condition of signal received from the probe is good.
ACTIVE SYSTEM LEDs (green)
The LEDs are lit green to show which system input (Probe 1 or Probe 2) is active. Providing the
relevant probe is in range and operational, it will be active as long as the LED is lit.
Off when system input is inactive.

OMI-2H installation guide
2.4
OMI-2H basics
OMI-2H inputs
Machine start inputs:
This LED will flash once when a machine control START signal is commanded.
Level 12 V to 30 V (10 mA at 24 V)
When the input is active, the probe is switched on.
The OMI-2H uses level machine inputs to define the active probe. When the respective input is active,
the probe is switched on.
If both inputs are active the system will default to error.
OMI-2H output
There is one output:
•Probe status (SSR).
Probe status (SSR):
•‘On’ resistance = 50 Wmax.
•Load voltage =40 V max.
•Load current = 100 mA max.
Switching time (with 10 mA load)
•Open to closed = 100 µs max.
•Closed to open = 25 µs max.
The probe status output indicates the status of the selected probe (only one probe can be selected at
a time).
The Low Battery, Probe Status, and Error LEDs will start flashing red when an output overload has
occurred. Probe status output will be triggered (SSR open). If this occurs, turn off the power supply
and remove the source of the problem. Turning on the power supply will reset the OMI-2H.
CAUTIONS:
Power supply voltage
Do not exceed 30 V between the black wire and the screen wire, or the red wire and screen wire, or
the red and black wires (power supply); as this could result in permanent damage to the OMI-2H and/
or the customer power supply.
The use of in-line fuses at the machine cabinet end is recommended to provide protection for the OMI-
2H and cable.
Screen connection
A good connection must be made to the machine ground (“star point”).
Output
Ensure the output from the OMI-2H does not exceed the specied current ratings.

2.5
OMI-2H basics
OMI-2H output waveform
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. for kinematic probes and 1 second max.
for strain gauge probes.
NOTE: An error will cause the SSR outputs to latch in the probe standby state until the start input is
reactivated.
Start inputs
SSR output
Probe 1
Probe 2
Common
Probe
switch
on
Seated
Probe
trigger
Probe
reseat
Triggered Seated
Low
battery Standby
Probe
switch
off
Standby
Probe
SSR open
SSR closed
Active
Inactive
Inactive
Active
Probe status
(level)
Normally closed

OMI-2H installation guide
2.6
OMI-2H basics
Switch SW2
SW2
NOTE: To gain access to the
switch, remove the window (for
more information see “Removing
the OMI-2H window” in Section
4, “Maintenance”).
ON
Switch SW2 output configuration
START Rx
RANGE RANGE
NOT USED NOT USED 50% 100%
NOT USED NOT USED 100% 50%

2.7
OMI-2H basics
Switch on / switch off
Switch on / switch off method
The OMI-2H operates using only optical on / optical off as the switch on / switch off method.
Optical on / optical off is available with all Renishaw’s OMP range of spindle probes and the optical tool
setter (OTS). Time out, spin on / spin off and shank on / shank off options are not compatible with the
OMI-2H.
Start up times
In normal operation the start up time for modulated probes is 410 ms max. for kinematic probes. For
strain gauge probes the start up time is 1 sec max.
The turn off time is 0 seconds.
Normal operation refers to when the on / off status of the probes is in synchronisation with the receiver
on / off status. The active probe should correspond to the respective active system LED.
When changing from Probe 1 to Probe 2, or Probe2 to Probe 1, allow 1 second between the
cancelling of one machine start input and raising of the other start input, also allow 1 second when
turning the probe off and back on again.
Synchronisation recovery
Under abnormal operating situations the system may lose synchronisation between the receiver and
probes. An internal synchronisation recovery will be initiated when the next machine input is received.
The maximum time for system recovery from an abnormal operating situation is 3.5 seconds. Such a
time delay could cause a machine alarm if controllers require ready signals within a time of less than
3.5 seconds.
NOTE: When used in conjunction with an OMP400 or OMP600, ensure the probe is set to the
standard switch-on delay.

OMI-2H installation guide
2.8
OMI-2H basics
OMI-2H dimensions
Dimensions given in mm (in)
46.7 (1.84)
16 (0.63)
84 (3.30)
40 (1.57) 40 (1.57)
40 (1.57)
45 (1.77)
63 (2.48)

2.9
OMI-2H basics
OMI-2H specification
Principal application The OMI-2H processes signals from RENGAGE™ or
standard probes, and converts them into machine outputs,
which are then transmitted to the CNC control. The system
allows two probes to be used with one interface.
Transmission type Infrared optical transmission (modulated)
Probes per system Two
Compatible probes OMP40-2, OMP40M, OLP40, OMP60, OMP60M, OMP400,
OMP600 and OTS
Operating range Up to 6 m (19.7 ft)
Weight OMI-2H including 8m (26.2ft) of cable = 720g (25.40 oz)
Supply voltage 12Vdc to 30Vdc (for more information, see “Wiring
diagram” in Section 3, “System installation”)
Supply current Transmitting: 160 mA max. peak
Receiving: 40 mA average
Note: @24 Vdc, all outputs open circuit.
M-code inputs Level 10 V to 30 V (10 mA @ 24 V)
Output signal Probe status
Voltage-free solid-state relay (SSR) output.
Switching time (with 10 mA load), open to closed 100 µs
max., closed to open 25 µs max.
Input / output protection Supply protected by resettable fuse.
Outputs protected by over current protection circuit.
Cable
(to machine
control)
Specification Ø5.8 mm (0.23 in), 6-core screened cable, each core
18 × 0.1 mm
Length 8 m (26.2 ft)
Diagnostic LEDs Start, low battery, probe status, error, active system and
signal condition.
Mounting Flush mounting or directional mounting with optional
mounting bracket (available separately).
Environment IP rating IPX8, BS EN 60529:1992+A2:2013
IK rating IK03, BS EN 62262:2002+A1:2021 [for glass window]
Storage temperature –25 °C to +70 °C (–13 °F to +158 °F)
Operating
temperature
+5°C to +55°C (+41°F to +131°F)

OMI-2H installation guide
2.10
OMI-2H basics
This page is intentionally left blank.

3.1
System installation
Mounting bracket (optional)
Dimensions given in mm (in)
25
(0.98)
25
(0.98)
19 (0.75)
38 (1.50)
3 holes Ø6.4 (0.25) 3 grip protrusions
100.5 (3.95)
2.0 (0.08)
30
(1.18)
25
(0.98)
45
(1.77)
45 (1.77) 45°
90 (3.54)
3 pairs of holes
Ø5.3 (0.20)
permit OMI-2H
mounting in
an alternative
orientation
2.0
(0.08)
NOTE: Install OMI-2H with cable exiting from lower side for good coolant run off.

OMI-2H installation guide
3.2
System installation
Wiring diagram
OMI-2H
CAUTIONS:
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.
The dc supply to this equipment must be derived from a source which is approved to
BSENIEC62368-1.
12 V to 30 V
0 V
Screen
Grey
Purple
White
Blue
Red
Black
Green/yellow
Probe status (SSR)
Machine start input (Probe 1)
Machine start input (Probe 2
Power supply (12 V to 30 V)
Machine ground (“star point”)