Rockwell Automation 1794-OF4I FLEX I/O Isolated Analog Output Module Installation - Manual (Page 4)

4 FLEX™ I/O Isolated Output Analog Module
Publication 1794-IN037E-EN-P - November 2011
Status Indicator
The OK status indicator is two-colored: red and green. The indicator flashes green
for one of three reasons:
1. The module configuration word is zero (for example, power up reset
condition).
2. The 24V DC user power is off.
3. The module is in configuration mode.
The indicator displays red to indicate that the module did not pass the initial
hardware test. Cycle power again.
After power up, if the status indicator is not flashing green or solid green, cycle
module power once more to verify a proper reset of the bus interface.
Specifications
Output Map
Dec 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Oct 17 16 15 14 13 12 11 10 7 6 5 4 3 2 1 0
Word 0 EN S1 S0 0 0 0 0 0 0 0 0 0 0 0 0 0
Word 1 Output data channel 0
Word 2 Output data channel 1
Word 3 Output data channel 2
Word 4 Output data channel 3
Word 5 Ch 3 configuration Ch 2 configuration Ch 1 configuration Ch 0 configuration
Word 6 IC 1 TR IT Q3 Q2 Q1 Q0 RV QK CK GO Channel number
Where: EN = Inable output; 0 = Output follows S1/S0, 1 = Output enabled 
S1/S0 = Safe state source 
IC = Initiate configuration bit 
TR = Transparent bit 
IT = Interrupt toggle bit 
Q0…Q3 = Requests for outputs to hold 
RV = Revert to default bit 
QK = Quick calibration 
CK = Calibration clock 
GO = Gain offset select
Configure the Output Channels
Configuration Bits Nominal Range Data Type Output Values Module Update
Rate
MSD LSD
0 0 0 1 4...20 mA Signed 2’s
complement <0000…7878> 5.0 ms
0 0 1 0 ±10V <831F…7CE1> 2.5 ms
0 0 1 1 ±5V <8618…79E8> 2.5 ms
0 1 0 0 0...20 mA Signed 2’s
complement % 0…10000> 5.0 ms
0 1 0 1 4…20 mA <0…10000> 5.0 ms
0 1 1 0 0…10V 0…10000 5.0 ms
0 1 1 1 ±10V <-10000…10000> 5.0 ms
1 0 0 0 0…20 mA Binary 0000…F3CF 2.5 ms
1 0 0 1 4…20 mA 0000…F0F1 5.0 ms
1 0 1 0 0…10V 0000…F9C2 2.5 ms
1 0 1 1 0…5V 0000…F3CF 2.5 ms
1 1 0 0 0…20 mA Offset binary <0618…F9E8> 2.5 ms
1 1 0 1 4…20 mA <8000…F878> 5.0 ms
1 1 1 0 ±10V <031F…FCE1> 2.5 ms
1 1 1 1 ±5V <0618…F9E8> 2.5 ms
General Specifications
Attribute Value
Number of outputs 4 isolated
Module location 1794-TB2, 1794-TB3, 1794-TB3S, 1794-TB3T, 1794-TB3TS, 1794-TBN
FlexBus voltage 5V DC
FlexBus current 50 mA
External DC power supply,
nom voltage range 24V DC 
19.2…31.2V DC (includes 5% AC ripple)
External DC power supply
current 210 mA @ 24V DC
Thermal dissipation, max 16 BTU/hr @ 31.2V DC
Power dissipation, max 4.7 W @ 31.2V DC
Isolation voltage 120V (continuous), Basic Insulation Type, channel to channel, channel to user,
channel to system, and user power to system when used with 1794-TB2,
1794-TB3, 1794-TB3S, 1794-TB3T, or 1794-TB3TS.
250V (continuous), Basic Insulation Type, channel to channel, channel to user,
channel to system, and user power to system when used with 1794-TBN.

Type tested at 1000V AC for 60 s.
Data format 2’s complement 
2’s complement % 
Binary 
Offset binary
Indicators 1 red/green power/status indicator
Keyswitch position 4
Dimensions, with module
installed in base; HxWxD 94.0 x 94.0 x 66.0 mm 
(3.7 x 3.7 x 2.6 in.)
Conductor category (1) 2 – on signal ports 
2 – on power ports
Conductor wire size Determined by installed terminal base
Wire type Shielded on signal ports
North American temp code T4A
IEC temp code T4
(1) Use this conductor category information for planning conductor routing. Refer to Industrial Automation Wiring and
Grounding Guidelines, publication
1770-4.1 .
Module Specifications – 1794-OF4I
Attribute Value
Resolution 
Voltage 
Current
15 bits plus sign 
0.320 mV/cnt 
0.656 mA/cnt
Conversion type Digital-to-analog converter
Update rate 2.5/5.0 ms all channels (see Configure the Output Channels table)
Output current terminal 0 mA output until module is configured 
4…20 mA (user configurable) 
0…20 mA (user configurable)
Output voltage terminal 0V output until module is configured 
±10V (user configurable) 
0…10V (user configurable) 
±5V (user configurable) 
0…5V (user configurable)
Step response to 63% of full
scale < 25 s
Current load on voltage
output, max 3 mA
Resistive load on voltage
output 0…750 
Absolute accuracy 
Voltage terminal 
Current terminal

0.1% full scale @ 25 °C

0.1% full scale @ 25 °C
Accuracy drift w/temperature 
Voltage terminal 
Current terminal

0.0012% full scale/°C

0.0025% full scale/°C
Calibration Factory calibrated; can be recalibrated when necessary.
Maximum overload 30V continuous or 32 mA continuous, one channel at a time.
Environmental Specifications
Attribute Value
Temperature, operating IEC 60068-2-1 (Test Ad, Operating Cold), 
IEC 60068-2-2 (Test Bd, Operating Dry Heat), 
IEC 60068-2-14 (Test Nb, Operating Thermal Shock): 
-20…55 °C (-4…131 °F)
Temperature, surrounding air,
max. 55 °C (131 °F)
Temperature, nonoperating IEC 60068-2-1 (Test Ab, Unpackaged Nonoperating Cold), 
IEC 60068-2-2 (Test Bb, Unpackaged Nonoperating Dry Heat), 
IEC 60068-2-14 (Test Na, Unpackaged Nonoperating Thermal Shock): 
-40…85 °C (-40…185 °F)
Relative humidity IEC 60068-2-30 (Test Db, Unpackaged Damp Heat): 
5…95% noncondensing
Vibration IEC60068-2-6 (Test Fc, Operating): 
5 g @ 10…500 Hz
Shock, operating IEC60068-2-27 (Test Ea, Unpackaged shock): 
30 g
Shock, nonoperating IEC60068-2-27 (Test Ea, Unpackaged shock): 
50 g
Emissions CISPR 11: 
Group 1, Class A (with appropriate enclosure)
ESD immunity IEC 61000-4-2: 
6 kV contact discharges 
8 kV air discharges
General Specifications