In order to protect the signal from outside noises induced in series mode and noises in common mode, we recommend you take the following precautions.
Use twisted shielded pairs with a minimum diameter of 0.28 mm2 (AWG24 gage).
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For modules fitted with a screw terminal block (TSX AEY 414 and TSX ASY 410):
Connect the each end of the cable shields to the shield continuation terminals (ground terminals).
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For modules fitted with Sub-D connector(s) (TSX AEY 16••/8••/420 and TSX ASY 800):
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Connection at the Sub-D connectors:
Given that there are a large number of channels, a cable of at least 13 twisted pairs is used, with general shielding (outside diameter 15 mm maximum), fitted with a male 25 pin Sub-D connector for direct connection to the module.
Connect the cable shielding to the cover of the male Sub-D connector. The controller is then grounded by the small tightening columns of the Sub-D connector. For this reason, it is required to screw the male Sub-D connector to its female base-plate.
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TELEFAST connection:
Connect the cable shielding to the terminals provided and the whole assembly to the cabinet ground.
Cable Connector Association
Multiple pairs of cables can be grouped for signals of the same type and with the same reference in relation to the ground.
Separate as far apart as possible the measuring wires of the discrete input / output cables (especially relay outputs) and cables that transmit "power" signals.
Reference of Sensors in Relation to the Ground
In order for the acquisition system to operate correctly, we recommend you follow the following precautions:
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the sensors must be close together (a few meters),
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all sensors must be referenced for a single point, which is connected to the ground of the module.
Using the Sensors Referenced in Relation to the Ground
The sensors are connected according to the following diagram:
If the sensors are referenced in relation to the ground, this may in some cases return a remote ground potential to the terminal or the Sub-D connector(s). It is therefore necessary to follow the following rules:
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this potential must be less than the safety voltage: for example, 48 V peak for France,
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setting a sensor point to a reference potential generates a leakage current. You must therefore check that all leakage currents generated do not disturb the system.
Using Pre-Actuators Referenced in Relation to the Ground
There are no specific technical constraints for referencing pre-actuators to the ground. For safety reasons, it is nevertheless preferable to avoid returning a remote ground potential to the terminal; this may be very different to the ground potential close by.
