DT80

Technical Specification

Analog Channels

5 analog input channels (expandable to 100*)

Each channel is independent and supports: one isolated 3-wire or 4-wire input, or two isolated 2-wire inputs, or three common referenced 2-wire inputs.

The following maximums apply.

Two wire with common reference terminal: 15 (expandable to 300*)

Two wire isolated: 10 (expandable to 200*)

Three and four wire isolated: 5 (expandable to 100*)

*Expansion requires optional CEM20 Fundamental Input Ranges

The fundamental inputs that the DT80 can measure are voltage, current, resistance and frequency. All other measurements are derived from these.

Sampling

Integrates over 50/60Hz line period for accuracy and noise rejection

Maximum sample speed: 25Hz

Effective resolution: 18 bits

Linearity: 0.01%

Common mode rejection: >90dB

Line series mode rejection: >35dB

Inputs

Inter-Channel Isolation: 100V (relay switching)

Analog Section Isolation: 100V (opto-isolated)

Input impedance: 100KΩ, >100MΩ

Common mode range: ・}3.5V or ・}35V on 30V range Sensor Excitation (Supply)

Analog channels:

selectable 250μA or 2.5mA precision current source, 4.5V voltage source, or switched external supply

General Purpose: Switchable 12V regulated supply for powering sensors & accessories (max 150mA)

Switchable 5V regulated supply for powering analog sensors (max 25mA)

Analog Sensors

Supports a wide range of sensors including, but not limited to, those listed below.

A wide range of sensor scaling and linearising facilities including polynomials, expressions and functions.

Thermocouples Types:

B, C, D, E, G, J, K, N, R, S, T

Calibration standard: ITS-90

RTDs

Materials supported: Pt, Ni, Cu

Resistance range: 10Ω to 10KΩ

Thermistors Types:

YSI 400xx Series, other types*

Resistance range: <10kΩ**

* Other thermistor types are supported by thermistor scaling and calculated channels.

**Resistance range can be increased with the use of a parallel resistor.

Monolithic Temperature Sensors Types supported:

LM34 - 60, AD590, 592, TMPxx, LM135, 235, 335

Strain Gauge and Bridge Sensors Configurations:

 . , . & full bridge Excitation: voltage or current

4-20mA

Current Loop Internal 100Ω shunt or external shunt resistor

Digital Channels

Digital Input/Outputs

8 bi-directional channels

Input Type: 8 logic level (max 20/30V)

Output Type: 4 with open drain FET(max: 30V, 100mA), 4 with logic output.

Relay Output 1 latching relay, contacts (max: 30Vdc, 1A)

Counter Channels

Low Speed Counters 8 counters shared with digital inputs.

Low speed counters do not function in sleep mode.

Size: 32 bit

Max Count rate: 10 Hz

Dedicated Counter Inputs 4 high speed or 2 phase encoder (quadrature) inputs

Size: 32 bit

Max Count rate: 100 kHz

Input type: 2 logic level inputs (max ・}30V), 2 sensitive inputs (10mV) for magnetic pick-ups (max ・}10V)

Serial Channels

SDI-12

4 SDI-12 inputs, shared with digital channels.

Each input can support multiple SDI-12 sensors.

Generic Serial Sensor

Flexible options to allow data to be logged from a wide range of smart sensors and data streams.

Available ports: Serial Sensor Port (RS232, RS422, RS485) or Host RS232 Port*

Baud rate: 300 to 115,200

*If used as a Serial Sensor channel then the Host Port is not available for other communications.

Calculated Channels Combine values from analog, digital and serial sensors using expressions involving variables and functions.

Functions: An extensive range of Arithmetic, Trigonometric, Relational, Logical and Statistical functions are available.