The following illustration shows the encoder interface on TM262M• references:
The encoder interface supports the following connection types:
oIncremental (RS422 (5 V or 24 V))
oAbsolute (SSI)
The advantage of using an Absolute (SSI) encoder for position detection is that the actual position of the moving object being monitored is always known. On power-up, or restart following a supply failure, the data provided by the encoder can therefore be used immediately by the controller.
The encoder interface can provide and control the encoder power supply.
The power supply to the encoder interface is provided by the controller through the embedded digital outputs power supply.
The table below shows the characteristics of the encoder:
|
Characteristics |
Description |
|
|---|---|---|
|
Inputs |
Rated input voltage |
5 Vdc |
|
Input voltage limits |
28.8 Vdc |
|
|
Rated input current |
1.5 mA @ 5 V 8 mA @ 24 V |
|
|
Input impedance |
2.85 kΩ |
|
|
Incremental Encoder |
Type of signal |
A+, A-, B+, B-, Z+, Z- |
|
Maximum operating frequency |
200 kHz |
|
|
Number of bits |
32, with configurable frame: oNumber of turns oNumber of bits/turn oBinary or gray format oParity |
|
|
SSI Encoder |
Clock frequency |
100 KHz, 250 KHz, or 500 KHz (selectable in EcoStruxure Machine Expert) |
|
Clock voltage |
5 Vdc |
|
|
Power supply to encoder (selectable in EcoStruxure Machine Expert) |
None, 5 Vdc, or 24 Vdc: |
|
|
None |
No power is supplied to the encoder. |
|
|
5 Vdc |
Nominal voltage: 5.1 Vdc ± 5 % Max. current: 200 mA Overcurrent and short circuit protection: No Encoder power return: Yes (selectable in EcoStruxure Machine Expert). Typical threshold: 2 V |
|
|
24 Vdc |
Use a regulated and smoothed power supply on the 24 Vdc power inputs of the CN8 terminal connector, with the specific characteristics of voltage limits and ripple factor specified for the encoder Nominal voltage: 24 Vdc with -0.7 Vdc typical internal voltage drop Max. current: 200 mA Overcurrent and short circuit protection: Yes. Max. current < 1.5 A Encoder power return: Yes (selectable in EcoStruxure Machine Expert). Typical threshold: 9 V |
|
|
Isolation |
Between encoder signals and internal logic |
550 Vac for 1 min. |
|
Connector |
Type |
Removable 15-pin Sub-D HD |
|
Insertion/removal durability |
> 100 times |
|
|
Cable |
Type |
Twisted pairs, shielded |
|
Length |
≤ 250 kHz: 100 m (328 ft) max. See Note below. 500 kHz: 50 m (164 ft) max. See Note below. |
|
NOTE: Calculation of Maximum Cable Length
Max. cable length [m] = Max. voltage drop for the cable [V] x Wire cross section (mm2) / (Encoder current [A] x 0.0171 (Ω mm²/m])
where:
Max. voltage drop for the cable = (Min. module output voltage - Min. encoder input voltage) / 2
Example:
Encoder consumes 100 mA with a 4.5…5.5 V supply
Min. module output voltage = 5.1 Vdc x 0.95 = 4.845 Vdc
Max. voltage drop for the cable = (4.845 Vdc - 4.5 Vdc) / 2 = 0.1725 Vdc
Max. cable length 0.14 mm2 = 0.1725 x 0.14 / (0.1 x 0.0171) = 14 m
Max. cable length 0.50 mm2 = 0.1725 x 0.50 / (0.1 x 0.0171) = 50 m
The encoder interface consists of a 15-pin Sub-D HD connector.
The following illustration describes the pins numbering:
The following table describes the pins of the encoder:
|
Description |
Encoder |
Pin |
Wire colors |
|---|---|---|---|
|
Incremental encoder |
A+ |
1 |
red/white |
|
A- |
2 |
brown |
|
|
Z+ |
4 |
orange |
|
|
Z- |
5 |
yellow |
|
|
B+ |
10 |
white |
|
|
B- |
11 |
purple |
|
|
Absolute (SSI) encoder |
SSI data + |
1 |
red/white |
|
SSI data - |
2 |
brown |
|
|
CLKSSI + |
6 |
green |
|
|
CLKSSI - |
14 |
light brown |
|
|
5 V Encoder supply |
+ 5 Vdc |
15 |
light purple |
|
0 Vdc |
8 |
pink |
|
|
24 V Encoder supply |
+ 24 Vdc |
7 |
blue |
|
0 Vdc |
8 |
pink |
|
|
Encoder power distribution feedback(1) |
Supply return |
13 |
light green |
|
Shielding |
|
Shell |
cable braided shield |
|
(1) Detection of encoder supply from controller. Default: Raised if signal is absent. |
|||
The following illustration describes the wiring diagram of an incremental encoder (RS422 / 24 Vdc) mounted on the encoder interface:
The following illustration describes the wiring diagram of an incremental encoder (RS422 / 5 Vdc or push-pull) mounted on the encoder interface:
The following illustration describes the wiring diagram of an absolute (SSI) encoder mounted on the encoder interface:
* Use a type T fuse appropriate for the load, not to exceed 2.5 A
