SDM-AO4

Name: SDM-AO4
Brand: Campbell Scientific
SKU: SDM-AO4
Availability: Discontinued

Analog Output Module

SDM-AO4

End of life

Analog Output Module

No longer available to order

This product is retained for service, documentation, and compatibility information.

Replaced by

SDM-AO4A
4-Channel Analog Output Module

Model:: SDM-AO4
Item Number:: SDM-AO4
Warranty:: 1 year

Overview

The SDM-AO4 is a synchronous device for measurement (SDM) that provides four analog outputs. Values in the data logger are transferred to the SDM-AO4 as digital values. The SDM-AO4 then performs a digital-to-analog conversion and outputs an analog voltage signal.

Technical Description

The SDM-AO4 provides four independent, continuous, analog outputs for proportional control or driving strip charts. Measured or processed values in the data logger are scaled to millivolts and transferred to the SDM-AO4 as digital values. The SDM-AO4 then performs a digital to analog conversion and outputs an analog voltage signal. The output voltage level is maintained until updated by the data logger.

SDM Operation

The data logger enables individual modules through an addressing scheme; multiple SDMs (in any combination) can be connected to one data logger. After a module is enabled, it operates independently of the data logger until additional commands are received or results are transmitted.

Benefits

Expands data logger current/voltage output capability
Supports proportional control or strip charts

Specifications

Analog Output Range: ±5000 mV
Analog Output Resolution: 2.5 mV
Output Resistance: 200 ohm
Accuracy: ±(0.5% of l V_out l +5 mV) for loads 75 kohm or greater
Operating Voltage: 9.6 to 16 Vdc
Typical Current Drain: 10.5 mA
Output Current: < 0.125 mA
Minimum Load: 75000 ohm

Accessories

(1)

CABLE5CBL
5-Conductor 22 AWG Cable with Drain
Orderable

Other Accessories

(1)

CABLE5CBL
5-Conductor 22 AWG Cable with Drain
This cable connects the SDM-AO4 to the datalogger. The CABLE5CBL is a 22 AWG, five conductor cable with a Santoprene jacket and an aluminum Mylar shield. A 1-ft cable length should be sufficient when both datalogger and SDM-AO4 are housed within an ENC12/14 enclosure; a 2-ft length may be required if the datalogger and SDM-AO4 are housed at opposite ends of an ENC16/18 enclosure.

CRBasic dataloggers should use the SDMSpeed instruction if the cable length is longer than 20 ft. The maximum recommended length for the CR7 is 600 ft. For other Edlog dataloggers, the maximum recommended cable length is 20 ft.
Orderable

Replacement Parts

(2)

Ships With

(2)

Similar Products

(3)

Compatibility

Data Logger Considerations

Up to 16 SDM devices can be connected to a single data logger.

Programming

The SDMAO4 Instruction controls the SDM-AO4 operation in CRBasic; Instruction 103 controls the SDM-AO4 operation in Edlog.

Power Supply

It is often convenient to power the SDM-AO4 from the data logger power supply, but when doing so consideration must be given to the SDM-AO4’s 10.5 mA continuous current drain. The alkaline supply available with the data logger has 7.5 Ahr and will power one SDM-AO4 for less than one month. This supply is not recommended for continuous long-term operation. The data logger’s sealed rechargeable power supply, float charged by an ac supply or solar panel, may be used for long-term operation.

The SDM-AO4 may also be powered from an external 12 V supply, independent from the data logger supply. The low side of an external 12 V supply should be connected to data logger ground and not directly to earth grounded.

Enclosure Considerations

The SDM-AO4 requires a desiccated, non-condensing environment; a Campbell Scientific enclosure is recommended. SDM-AO4 serial numbers 2145 or higher have built-in keyhole flanges for mounting to the backplates of Campbell Scientific enclosures; the first unit to use these flanges was shipped in 18 September 1997. Grommets and screws are provided to attach the flanges/bracket to the backplate of our enclosures. Older SDM-AO4s required our 6279 SDM-AO4 Mounting Bracket (now retired) for this purpose.