Allen-Bradley offers both discrete (digital) and analog Input and Output modules of various capabilities. The digital Input/Output modules feature a discrete signal that is either on or off, such as the input of limit switches or the output signal to a relay. Conversely, analog Input/Output modules convert voltage or current to point-in-time values via the processor, such as the input received by a thermocouple or the output signal of a pressure regulator. Virtually all SLC 500 Systems will incorporate the use of both discrete and analog Input and Output modules.
The SLC 500 System delineates between the various discrete modules by sorting them into two categories: Sinking and Sourcing. As an engineer designing your own system it will help you to understand the difference between these two options. Here is the definition as given by Allen-Bradley:
To maintain electrical compatibility between field devices and the programmable controller system, this definition is extended to the input/output circuits on the discrete I/O modules.
The following tables will help you to compare the Discrete Input/Output modules available in the Allen-Bradley SLC 500 System as well as the Analog Input/Output modules:
| PART NUMBER |
1746-OG16 |
1746-OV8 |
1746-OV16 |
1746-OV32 |
1746-OVP16 |
| # OF OUTPUTS |
16 |
8 |
16 |
32 |
16 |
| POINTS/COMMON |
16 |
8 |
16 |
16 |
16 |
| VOLTAGE |
5V DC |
24V DC |
24V DC |
24V DC |
24V DC |
| OPERATING VOLTAGE RANGE |
4.5-5.5V DC |
10-50V DC |
10-50V DC |
5-50V DC |
20.4-26.4V DC |
| CURRENT @ 5V |
180 mA |
135 mA |
270 mA |
190 mA |
250 mA |
| CURRENT @ 24V |
0 mA |
0 mA |
0 mA |
0 mA |
0 mA |
| VOLTAGE DROP, ON-STATE OUTPUT, MAX. |
– |
1.2 V @ 1.0 A |
1.2 V @ 0.5 A |
1.2V @0.5 A |
1.0 V @ 1.0 A |
| LOAD CURRENT, MIN. |
0.15 mA |
1 mA |
1 mA |
1 mA |
1 mA |
| LEAKAGE CURRENT, OFF-STATE OUTPUT, MAX. |
0.1 mA |
1 mA |
1 mA |
1 mA |
1 mA |
| SIGNAL ON DELAY, MAX. (RESISTIVE LOAD) |
0.25 ms |
0.1 ms |
0.1 ms |
0.1 ms |
0.1 ms |
SIGNAL OFF DELAY, MAX.
(RESISTIVE LOAD) |
0.50 ms |
1.0 ms |
1.0 ms |
1.0 ms |
1.0 ms |
CONTINUOUS CURRENT
PER MODULE |
N/A |
8.0 A (30°C)
4.0 A (60°C) |
8.0 A (30°C)
4.0 A (60°C) |
8.0 A (0-60°C) |
6.4 A (0-60°C) |
CONTIUOUS CURRENT
PER POINT |
24 mA |
1.0 A (30°C)
0.5 A (60°C) |
0.50 A (30°C)
0.25 A (60°C) |
0.50 A (30°C)
0.25 A (60°C) |
1.5 A (30°C)
1.0 A (60°C) |
| SURGE CURRENT PER POINT FOR 10 ms |
N/A |
3.0 A |
3.0 A |
1.0 A (30°C)
1.0 A (60°C) |
4.0 A+ |
| PART NUMBER |
1746-OB6EI |
1746-OB8 |
1746-OB16 |
1746-OB16E |
1746-OB32 |
1746-OB32E |
1746-OBP8 |
1746-OBP16 |
| # OF OUTPUTS |
6 EP |
8 |
16 |
16 EP |
32 |
32 EP |
8 |
16 |
POINTS/
COMMON |
IND. ISOLATED |
8 |
16 |
16 |
16 |
16 |
4 |
16 |
| VOLTAGE |
24V DC |
24V DC |
24V DC |
24V DC |
24V DC |
24V DC |
24V DC |
24V DC |
| OPERATING VOLTAGE RANGE |
10-30 V DC |
10-50V DC |
10-50V DC |
10-30V DC |
5-50V DC |
10-30V DC |
20.4-26.4V DC |
20.4-26.4V DC |
| CURRENT @ 5V |
46mA |
135 mA |
280 mA |
135 mA |
190 mA |
190 mA |
135 mA |
250 mA |
| CURRENT @ 24V |
0 mA |
0 mA |
0 mA |
0 mA |
0 mA |
0 mA |
0 mA |
0 mA |
| VOLTAGE DROP. ON-STATE OUTPUT, MAX. |
1.0V @
2.0 A |
1.2V @
1.0 A |
1.2V @
0.5A |
1.0V @
0.5 A |
1.2V @
0.5 A |
1.2V @
0.5 A |
1.0V @
2.0 A |
1.0V @
1.0 A |
| LOAD CURRENT, MIN. |
1 mA |
1 mA |
1 mA |
1 mA |
1 mA |
1 mA |
1 mA |
1 mA |
| LEAKAGE CURRENT, OFF-STATE OUTPUT. MAX. |
1 mA § |
1 mA § |
1 mA § |
1 mA § |
1 mA |
1 mA |
1 mA § |
1 mA § |
| SIGNAL ON DELAY, MAX. (RESISTIVE LOAD) |
1.0 ms |
0.1 ms |
0.1 ms |
1.0 ms |
0.1 ms |
1.0 ms |
1.0 ms |
0.1 ms |
| SIGNAL OFF DELAY, MAX. (RESISTIVE LOAD) |
2.0 ms |
1.0 ms |
1.0 ms |
1.0 ms |
1.0 ms |
2.0 ms |
2.0 ms |
1.0 ms |
| CONTINUOUS CURRENT PER MODULES |
12.0 A
(0-60°C) |
8.0 A (30°C)
4.0 A (60°C) |
8.0 A (30°C)
4.0 A (60°C) |
8.0 A
(0-60°C) |
8.0 A
(0-60°C) |
8.0 A
(0-60°C) |
8.0 A
(0-60°C) |
6.4 A
(0-60°C) |
| CONTINUOUS CURRENT PER POINT |
2.0 A
(0-60°C) |
1.0 A (30°C)
0.50 A (60°C) |
0.50 A (30°C)
0.25 A (60°) |
1.0 A (30°)
0.50 A (60°C) |
0.50 A (30°C)
0.25 A (60°C) |
0.50 A (30°C)
0.25 A (60°C) |
2.0 A
(0-60°C) |
1.5 A (30°C)
1.0 A (60°C) |
| SURGE CURRENT PER POINT FOR 10 ms |
4.0 A |
3.0 A |
3.0 A |
2.0 A |
1.0 A (30°C)
1.0 A (60°C) |
1.0 A (30°C)
1.0 A (60°C) |
4.0 A |
4.0 A |
| PART NUMBER |
1746-OA8 |
1746-OA16 |
1746-OAP12 |
| # OF OUTPUTS |
8 |
16 |
12 |
| POINTS/COMMON |
4 |
8 |
6 |
| VOLTAGE |
120/240 VAC |
120/240 VAC |
120/240 VAC |
| OPERATING VOLTAGE RANGE |
85-265 VAC @ 47-63Hz |
85-265 VAC @ 47-63Hz |
85-265 VAC @ 47-63Hz |
| CURRENT @ 5V |
185 mA |
370 mA |
370 mA |
| CURRENT @ 24V |
0 mA |
0 mA |
0 mA |
| VOLTAGE DROP, ON-STATE OUTPUT, MAX. |
1.50 V @ 1.0 A |
1.50 V @ 0.50 A |
1.2 V @ 2.0 A |
| LOAD CURRENT, MIN. |
10 mA |
10 mA |
10 mA |
| LEAKAGE CURRENT, OFF-STATE OUTPUT, MAX. |
2 mA |
2 mA |
2 mA |
| SURGE CURRENT PER POINT |
10.0 A for 25 ms |
10.0 A for 25 ms |
17.0 A for 25 ms |
SIGNAL ON DELAY, MAX.
(RESISTIVE LOAD) |
1 ms |
1 ms |
1 ms |
SIGNAL OFF DELAY, MAX.
(RESISTIVE LOAD) |
11 ms |
11 ms |
11 ms |
| CONTINUOUS CURRENT PER POINT |
1.0 A @ 30° C
0.50 A @ 60° C |
0.50 A @ 30° C
0.25 A @ 60° C |
2.0 A @ 30 ° C
1.25 A @ 55° C
1.0 A @ 60° C |
CONTINUOUS CURRENT
PER MODULE |
8.0 A @ 30° C
4.0 A @ 60° C |
8.0 A @ 30° C
4.0 A @ 60° C |
9.0 A @ 30° C
6.0 A @ 60° C |
| PART NUMBER |
FUNCTION |
CURRENT/
VOLTAGE |
I/O
CHANNELS |
DESCRIPTION |
| 1746-NI4 |
INPUT |
-20 TO + 20 mA
-10 TO + 10 VDC |
4 |
HIGH RESOLUTION INPUT
CURRENT/VOLTAGE |
| 1746-NI8 |
INPUT |
-20 TO + 20 mA
-10 TO + 10 VDC |
8 |
HIGH RESOLUTION INPUT
CURRENT/VOLTAGE |
| 1746-NI16I |
INPUT |
-20 TO +20 mA |
16 |
HIGH RESOLUTION INPUT
CURRENT |
| 1746-NI16V |
INPUT |
-10 TO +10 VDC |
16 |
HIGH RESOLUTION INPUT
VOLTAGE |
| 1746-NIO4I |
INPUT/OUTPUT |
-20 TO + 20 mA or
-10 TO + 10 VDC INPUT;
0 TO 20 mA OUTPUT |
2 INPUT;
2 OUTPUT |
HIGH RESOLUTION INPUT
CURRENT/VOLTAGE;
CURRENT OUTPUT |
| 1746-NIO4V |
INPUT/OUTPUT |
-20 TO + 20 mA or
-10 TO + 10 VDC INPUT; -10 TO +10 VDC OUTPUT |
2 INPUT;
2 OUTPUT |
HIGH RESOLUTION INPUT
CURRENT/VOLTAGE;
VOLTAGE OUTPUT |
| 1746-FIO4I |
INPUT/OUTPUT |
0 TO 20 mA or
0 TO 10 VDC INPUT;
0 TO 20 mA OUTPUT |
2 INPUT;
2 OUTPUT |
FAST ANALOG INPUT;
ANALOG CURRENT OUTPUT |
| 1746-FIO4V |
INPUT/OUTPUT |
0 TO 20 mA or
0 TO 10 VDC INPUT;
-10 TO +10 VDC OUTPUT |
2 INPUT;
2 OUTPUT |
FAST ANALOG INPUT;
ANALOG VOLTAGE OUTPUT |
| 1746-NO4I |
OUTPUT |
0 TO 20 mA |
4 |
CURRENT OUTPUT |
| 1746-NO4V |
OUTPUT |
-10 TO +10 VDC |
4 |
VOLTAGE OUTPUT |
| 1746-NO8I |
OUTPUT |
0 TO 20 mA |
8 |
CURRENT OUTPUT |
| 1746-NO8V |
OUTPUT |
-10 TO +10 VDC |
8 |
VOLTAGE OUTPUT |
| 1746-NT4 |
INPUT |
60 mA / 5V
40 mA /24V |
4
+ CJC SENSOR |
THERMOCOUPLE INPUT
TYPES J, K, T, E, R, S, B, N |
| 1746-NT8 |
INPUT |
120 mA/5 V
70 mA/24 V |
8
+ CJC SENSOR |
THERMOCOUPLE INPUT
TYPES J, K, T, E, R, S, B, N |
| 1746-INT4 |
INPUT |
110 mA/5 V
85 mA/24 V |
4
+ CJC SENSOR |
THERMOCOUPLE INPUT
TYPES J, K, T, E, R, S, B, N, C, D |
| 1746-NR4 |
INPUT |
50 mA/5 V
50 mA/24 V |
4 |
RTD/RESISTANCE INPUT |
| 1746-NR8 |
INPUT |
100 mA/5 V
55 mA/24 V |
8 |
RTD/RESISTANCEINPUT |
| 1746-HSCE |
INPUT |
DIFF: 0 TO 5 VDC;
SE: ±5 VDC TO 30 VDC |
1 SET ±A, ±B, ±Z DIFF; 5 VDC, 12 VDC, 24 VDC SE |
HIGH SPEED COUNTER WITH
DIFFERENTIAL (DIFF) OR
SINGLE-ENDED (SE) INPUTS |
| 1746-HSCE2 |
INPUT |
5 VDC TO 30 VDC |
2 SETS ±A, ±B,±Z; 2 ENCODERS; 4 PULSE DIFF OR SE |
HIGH SPEED COUNTER WITH DIFF, SE, OR ENCODER INPUTS |
| 1746-BLM |
INPUT/OUTPUT |
110mA/5 V |
4 DIS/4 ANA INPUT;
4 DIS/4 ANA & 1 EXCITATION OUTPUT |
BLOW MOLDING I/O WITH DISCRETE & ANALOG INPUTS/OUTPUTS |
| 1746-BTM |
INPUT |
-50 TO +50 mV;
-100 TO + 100 mV |
4 |
BARREL TEMPERATURE MODULE |
| 1746-HSTP1 |
INPUT/OUTPUT |
200 mA/5 V |
5 VDC DIFF/12-24 VDC SE INPUT; DIGITAL OUTPUT |
STEPPER CONTROL
MODULE |
| 1746-HSRV |
INPUT/OUTPUT |
300 mA/5 V |
3 INPUT
1 OUTPUT |
SERVO CONTROL
MODULE |
| 1746-QV |
INPUT/OUTPUT |
250 mA/5 V |
1 INPUT
1 OUTPUT |
OPEN-LOOP VELOCITY MODULE/HYDRAULICS |
| 1746-QS |
INPUT/OUTPUT |
1000 mA/5 V
200 mA/24 V |
4 INPUT
4 OUTPUT |
CLOSED LOOP SERVO POSITIONING FOR SYNCHRONIZED AXES |
