schmersal PSC1 - Connection of Position and Speed Sensors; General Instructions

Installation manual
HB-37420-810-01-25F-EN PSC1-C-100 Installation manual - V2.2.docx Page 126 of 201
Version: 25F
5.11 Connection of position and speed sensors
5.11.1 General instructions
Depending on the module type, the PSC1-C-100 axis expansion modules (PSC1-E-21-SDM1,
PSC1-E-22-SDM1-2, PSC1-E-23-SDM2, PSC1-E-24-SDM2-2) have (2/4) external encoder
interfaces for the connection of the usual industrial incremental and absolute encoders. The
encoder interfaces can be configured for incremental, SIN/COS, absolute SSI encoders or for
proximity switches.
In addition, it is possible to connect two sensors that generate incremental signals (for instance
proximity switches or HTL signals) to the counter inputs on the PSC1 module.
The signals must be read using a normal track and a complementary track.
IMPORTANT:
Power is supplied to the encoder system via the terminals provided on the PSC1 module. This
voltage is supplied to the encoder connector and is monitored by an internal diagnostic process.
If the sensor is supplied with an external voltage, this must be routed via the encoder connector.
The related terminal (encoder power supply) on the PSC1 module remains unused.
If an external sensor supply voltage is not fed back via the encoder connector, the failure of this
supply must be included in the fault analysis for the overall system. In particular, it is therefore
necessary to demonstrate that if the specified operating voltage for the encoder system is
dropped below / exceeded, this fault will be detected or can be excluded.
EMC measures such as screening etc. are to be observed.
The two encoders must not interact with each other. This applies for both the electrical and the
mechanical part.
If both encoders are coupled to the device to be monitored via common mechanical parts, the
connection must be of a positively locking design and there must not be any parts subject to
wear (chains, toothed belts etc.). If this is nevertheless the case, additional monitoring devices
for the mechanical connection of the sensors are required (e.g. monitoring a toothed belt).
If position processing is active, at least one absolute encoder must be used.
On the usage of two equivalent sensors it is to be ensured that the sensor with the higher
resolution is configured as sensor1 (process sensor) and the sensor with the lower resolution as
sensor 2 (reference sensor).
Safety instructions:
• The GND connections for the encoders are to be connected to GND on the PSC1.