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Installation Instructions
Bulletin 842-SPA Serial to Parallel Adaptor
IMPORTANT: SAVE THESE INSTRUCTIONS FOR FUTURE USE.
Specifications
Size 103 x 165mm (4 x 6.5in)
Voltage Supply 11-32V DC
Supply Current 250mA (without load)
Operating Temperature
Output Driver (parallel) PushĆpull, 10-32V, 35mA (max)
Input (SSI) RS422
Maximum SSI Cable Length 350m @ 125kHz; 25m @ 500kHz
0_C to 50_C (32_F to 122_F)
Mounting Instructions
1. Locate and mount the 842–CH cardholder (purchased
separately) close to the controller. See the Dimensions
section to determine the 842–CH card holder hole
locations.
2. Wire the connections according to the a) Electrical
Connections b) Jumpers Needed and c) Direction Control
sections using wire size 26–16 AWG.
IMPORTANT: Wiring must be in accordance with the
National Electric Code and applicable local
codes and ordinances.
3. Insert the 842–SPA into the cardholder. Set the Hex
Function switch on the 842–SPA to the appropriate setting
as shown in Table 1 below:
Switch
Setting
4 500kHz Binary Binary
4 500kHz Gray Gray
5 125kHz Binary Binary
5 125kHz Gray Gray
6 500kHz Gray Binary
7 125kHz Gray Binary
4. Apply power supply of 11–32V DC to the 842–SPA.
5. The 842–SPA begins sending clock pulses and receives
data pulses in the synchronous serial interface (SSI)
format. An example timing diagram is in the Timing
Diagrams section.
6. The parallel output data can be found on the following bits
according to Table 2 below:
842A Encoder
Type
A 8192 1-13 2048 14-24
B 4096 1-12 4096 13-24
C 2048 1-11 8192 12-24
D 4096 1-12 512 13-21
E 4096 1-12 256 13-20
Clock
Frequency
Pulses
Per Rev.
Bits Used
LSB-MSB
SSI
Input
No. of
Revs.
Parallel
Output
Bits Used
LSB-MSB
Electrical Connections
Type Function 842-CH Terminal
842-SPA and Output Driver
Ground
842-SPA Power
Power & Ground
SSI
Parallel Output
See Table 2 for
Bit Distribution
Ê Terminals are connected internally on the 842-SPA.
Ë The Error Bit is normally logic 0. If there is a power interruption (i. e. - low voltage)
during data transmission, the Error Bit is set to logic 1.
Parallel Output Driver
Power
Encoder Power 32A
Encoder Ground
Data + 26C
Data - 26A
Clock + 27C
Clock - 27A
Error Bit
Bit 1 3C
Bit 2 3A
Bit 3 4C
Bit 4 4A
Bit 5 5C
Bit 6 5A
Bit 7 6C
Bit 8 6A
Bit 9 7C
Bit 10 7A
Bit 11 8C
Bit 12 8A
Bit 13 9C
Bit 14 9A
Bit 15 14C
Bit 16 14A
Bit 17 15C
Bit 18 15A
Bit 19 16C
Bit 20 16A
Bit 21 17C
Bit 22 17A
Bit 23 18C
Bit 24 18A
1A, 2C, 25AÊ
32C,13CÊ
31A
1C,25CÊ
2AË
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Jumpers Needed
Connect the following three jumpers:
1. 842–SPA Ground (Terminal 1A) to Encoder Ground
(Terminal 1C)
2. 842–SPA Power (32C) to Encoder Power (32A)
3. 842–SPA Power (13C) to Parallel Output Driver Power
(31A)
Direction Control
When pin 12 of the encoder is connected to DC + (or left
floating), the 842A will count UP when the shaft is turned CW
when looking at the shaft. When pin 12 is connected to DC
return, the 842A will count UP when the shaft is turned in the
CCW direction when looking at the shaft.
11
BITS
842–SPA
CLOCK +
842A
SSI
DATA +
VALUE
423 6579 1819202122
1
0
1
0
1
0000000001 1 11 11100 00000
8
TURNS
10
1314151617
12
1
Timing Diagrams
Below is an example of a timing diagram as viewed on an
oscilloscope. In this example, the 842A–31NB, a binary code
output with 4096 pulses per revolution and 4096 turns is
connected to an 842–SPA serial to parallel interface adaptor.
The 842–SPA generates an SSI clock burst of pulses. On the
positive slope of the start pulse, the 842A–31NB begins to
transmit its position data. In the example below, the
842A–31NB is returning 100000000011 (2051 Turns) and
001100000111 (775 position). After the data is sent, the output
remains in a low state for a short duration, then goes to a high
state in anticipation of the next SSI clock burst. The Error Bit
(bit 25) is normally zero. If there is a power interruption (e. g. –
low voltage) during data transmission, the Error Bit is set high.
23
25
SHAFT POSITION
24
ERROR BIT
1
...
...
Dimensions
Use the figure below to locate the mounting holes of the 842–CH.
131
(5.16)
121
(4.76)
"A" Terminals
45
(1.77)
76
(2.99)
24
(0.95)
"C" Terminals
...9 7 5 3 131
...8 6 4 232
5.5
(0.22) Dia.
15 (0.59)
30
(1.18)
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Publication 75008–134–01(E)
Document 910 990 103 490
August 2001
Printed in Germany