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Simplified Chinese Sensor Identify & Connecting
Homing Switch Overview
This document assumes the switch or sensor is being used for homing, but the information also applies to all switch and sensor types.
This document provides guidance on wiring and input configuration based on the type of switch or sensor being used. Due to the wide variety of sensors available, individual support for specific third-party sensors cannot be provided. This guide is intended to help you identify and correctly connect your chosen sensor or switch using basic testing and reference information. It should be used together with the documentation supplied by the sensor manufacturer.
This document also explains how to identify electronic sensors such as proximity, optical, and Hall-effect sensors using a voltmeter and simple testing procedures.
Wiring examples for mechanical switches, including lever switches, push buttons, and magnetic reed switches, are provided later in this document. A continuity tester should be used to determine whether a mechanical switch is normally open or normally closed, and normally closed wiring should always be used where possible for improved safety.
Powering your Homing Sensors
Power for homing sensors on MASSO G3 and MASSO G3 Touch controllers can be supplied from the main DC power supply distribution point, from a separate power supply that shares a common ground with MASSO, or from the auxiliary power terminals on the controller. The auxiliary power terminals are the red and black terminals located between the input and output terminals.
MASSO Homing Sensor
Identify your Electronic homing switch type
Electronic homing sensors can be identified using a simple voltage test. The process below helps determine the sensor type and the required wiring and input configuration.
First, connect the sensor to a suitable power supply according to the manufacturer’s specifications.
With the sensor in its normal, untriggered state, measure the voltage between the sensor output and the positive supply, and then between the sensor output and the negative supply. If the measured voltage is greater than 3.5 volts, record the result as 1. If it is less than 3.5 volts, record the result as 0. Voltage polarity on the meter can be ignored.
Next, trigger the sensor and repeat the same voltage measurements. Again, record a value of 1 for voltages greater than 3.5 volts and 0 for voltages below 3.5 volts.
Electronic Homing Switch Matrix
Output to -ve | Output to +ve | ||
Normal State |
|
| If the measured voltage in 3.5 volts |
Triggered State |
Once the measurements are complete, compare your results to the matching sensor type table and follow the indicated wiring and input configuration for that sensor type.
Sensor Types and Wiring
Type 1 Sensor
Output to -ve | Output to +ve | |
Normal State | 0 | 1 |
Triggered State | 1 | 0 |
Type 2 Sensor
Output to -ve | Output to +ve | |
Normal State | 1 | 0 |
Triggered State | 0 | 1 |
Type 3 Sensor
Output to -ve | Output to +ve | |
Normal State | 0 | 0 |
Triggered State | 1 | 0 |
Type 4 Sensor
Output to -ve | Output to +ve | |
Normal State | 0 | 0 |
Triggered State | 0 | 1 |
Type 5 Sensor
Output to -ve | Output to +ve | |
Normal State | 1 | 0 |
Triggered State | 0 | 0 |
Mechanical Homing Switch Connection
Mechanical switches can be wired in two ways, but the preferred and safer method is to use a normally closed switch. If a normally closed switch wire breaks, the homing input will go high, causing MASSO to detect the switch as active and back off safely before stopping.
If a normally open switch wire breaks, the input state does not change, and MASSO may drive the axis the full travel distance before generating a homing alarm.
Additional Resourses
For further information on homing configuration and setup, refer to the MASSO homing documentation.
Detailed video on setting up Homing settings in MASSO
Mounting the Homing Sensor
Homing sensors and limit switches are traditionally mounted at the extreme ends of axis travel and wired individually back to the controller. This approach increases wiring complexity and uses additional controller inputs.
Homing sensors work very effectively when used together with soft limits. When a homing sensor is also used as a hard limit sensor, it is recommended that the sensor be mounted on the moving carriage, with fixed triggers positioned at each end of axis travel. This allows a single sensor to be used for both homing and hard limit detection while minimising wiring and hardware.
The trigger must be designed so that the sensor remains in the active state for the full duration of the homing process.
Example axis with the sensor mounted on the moving carriage and the trigger mounted on the stationary rail
Multiplexing Homing Sensors on the Same Axis
If an existing machine has homing or limit sensors at both ends of an axis, these sensors can be multiplexed and connected to a single homing input on MASSO.
The method used to multiplex sensors depends on the sensor type. Different sensor types must not be mixed on the same axis. Some sensor types, such as Type 5 sensors, cannot be multiplexed because they do not output a signal when triggered.
When wired correctly, triggering either sensor will cause the homing input to change from Low to High.
For the correct multiplexing method for your specific sensor type, consult the sensor manufacturer’s documentation.
Example of how multiple homing sensors may be multiplexed
