Campbell Scientific AM16/32B AM16/32B Relay Multiplexer - Page 14

AM16/32B Relay Multiplexer

Dimensions

Length:

23.9 cm (9.4 in)

Width:

10.2 cm (4.0 in)

Depth:

4.6 cm (1.8 in)

Weight:

693 g (1.5 lb) (approx.)

Mounting Tab

Hole Spacing:

1 x 3 x 9 in.

Up to 1/8 in or 3 mm diameter

screws (see FIGURE 8-1).

Expandability

**

(nominal):

2 AM16/32Bs per CR800/CR850

4 AM16/32Bs per CR3000



4 AM16/32Bs per CR23X

4 AM16/32Bs per CR10(X)

4 AM16/32Bs per 21X

8 AM16/32Bs per CR7 725 Card

Maximum Cable Length:

Depends on sensor and scan rate.

In general,

longer lead lengths necessitate longer

measurement delays.

Refer to datalogger

manual for details.

Maximum

Switching Current

***

:

500 mA

Contact Specifications

Initial contact resistance:

<0.1 ohm max.

Initial contact bounce:

<1 ms

Contact material:

Gold clad silver alloy

Wiper to N.O. contact

capacitance:

0.5 pF

Typical low-current

(<30 mA) life:

5 x 10

7

operations

Relay Switching

Thermal emf:

0.3 μV typical; 0.5 μV maximum

Characteristics (applying 11.3 – 14 Vdc)

Operate time:

<10 ms over temperature and supply ranges

Break-before-make guaranteed by design.

Relays disengage from previous selected

channel before engaging next channel.

ESD

Air Discharge:

complies with IEC61000-4-2, test level 4

(±15 kV)

Contact Discharge:

complies with IEC61000-4-2, test level 4

(±8 kV)

4

Section	Page
Revision and Copyright Information	1
Warranty	3
Assistance	4
Table of Contents	5
1. Function	11
1.1 Typical Applications	11
1.2 Compatibility	12
2. Physical Description	12
3. AM16/32B Specifications	13
4. Operation	15
4.1 The Control Terminals	15
4.1.1 Reset	16
4.1.2 Clock	17
4.1.2.1 Mode A	17
4.1.2.2 Mode B	17
4.1.2.3 Datalogger Connection/Instruction	18
4.1.3 Ground	19
4.1.4 Power Supply	19
4.2 Measurement Terminals	20
4.2.1 COM Terminals	21
4.2.2 Sensor Input Terminals	21
5. Datalogger Programming	22
5.1 CRBasic Programming	23
5.1.1 CR1000, CR800, and CR850 Programming	24
5.1.2 CR5000 and CR3000 Programming	26
5.2 Edlog Programming	27
5.2.1 Single Loop Instruction Sequence	27
5.2.2 Multiple Loop Instruction Sequence	32
5.3 General Programming Considerations	34
6. Sensor Hookup and Measurement Examples	34
6.1 Single-Ended Analog Measurement without Sensor Excitation	35
6.2 Differential Analog Measurement without Sensor Excitation	35
6.3 Half Bridge Measurements	36
6.3.1 Half Bridge Measurement with Completion Resistor at Datalogger	36
6.3.2 Potentiometer Measurement	37
6.3.3 Four Wire Half Bridge (Measured Excitation Current)	37
6.4 Full Bridge Measurements	38
6.5 Full Bridges with Excitation Compensation	39
6.6 Thermocouple Measurement	40
6.6.1 Measurement Considerations	40
6.6.2 Single-ended Thermocouple Measurement	42
6.6.3 Differential Thermocouple Measurement	43
6.7 Mixed Sensor Types	43
6.7.1 Mixed Sensor Example: Soil Moisture Blocks and Thermocouples	43
7. General Measurement Considerations	47
8. Installation	47
8.1 Mounting Tabs	48
8.2 Controlling Humidity	48
Appendix A. AM16/32B Improvements	49

Campbell Scientific AM16/32B AM16/32B Relay Multiplexer - Page 14

Wiper to N.O. contact

Page 14 highlights