Introduction

The TSX CCY 1128 module inputs are able to receive signals from the following encoders:

  • incremental,

  • absolute with SSI serial outputs,

  • absolute with parallel outputs. This last type requires the use of a specific interface TELEFAST ABE-7CPA11.

The user can choose from these encoder types according to the requirements.

Encoder output interface

The table below summarizes the main characteristics of the output interface for the encoder types normally used.

Type

of encoder

Supply

voltage

Output

voltage

Types of interface

Incremental

5 VDC

5 VDC differential

Outputs with line transmitters to RS 422 standard, with 2 outputs per signal A+/A-, B+/B-, Z+/Z-

10...30 VDC

10...30 VDC

Totem Pole outputs with one output per signal A, B, Z

Absolute with SSI outputs

10...30 VDC

5 VDC differential

Output with line transmitters to RS 422 standard for the data signal (Data SSI)

RS 422 compatible input for the clock signal (CLK SSI).

Absolute with parallel outputs

5 VDC or

10...30 VDC

5 VDC or 10...30 VDC

Parallel outputs. Require the use of the Telefast ABE-7CPA11 interface to transform parallel output signals into serial signals.

Encoder supply

The design of the module allows an encoder supply of:

  • 5 VDC

  • 24 VDC, standardized voltage in the 10…30 VDC format.

The choice of supply voltage is dependent on the encoder supply voltage.

5 VDC encoder supply

For encoders with a 5 VDC supply, voltage falls must be taken into account. These are dependent upon:

  • the length of the cable between the module and the encoder (double length),

  • the section of wire,

  • the encoder consumption.

The acceptable voltage fall for the encoder is generally 10% of the nominal voltage.

The table below gives the on-line voltage fall, according to the section of the wire, for a 100 meter length of wire with a given encoder consumption.

Section of wire

Voltage fall for a 100 meter length of wire with an encoder consumption of:

50 mA

100 mA

150 mA

200 mA

0.22 mm = gauge 24

0.4 V

-

-

-

0.34 mm = gauge 22

0.25 V

0.5 V

-

-

0.5 mm

0.17 V

0.34 V

0.51 V

-

1 mm

0.09 V

0.17 V

0.24 V

0.34 V

24 VDC encoder supply

Encoders with a supply voltage of 24 VDC are recommended for the following reasons:

  • the supply source does not need to be completely accurate. As a general rule, these encoders use a supply format of 10…30 V.

  • an on-line voltage fall is of little significance due to a substantial distance between the module and the encoder.

Ground connection continuity

In order to ensure correct operation during interference, it is vital:

  • to choose an encoder with a metal casing that is referenced to the protective ground of the connected device.

  • that the ground connection is continuous between:

    • the encoder,

    • the shielding of the connector cable,

    • the module.