dataTaker - Data Loggers, Powerful and Flexible Data Acquisition & Data Logging Systems

Powering Sensors from the dataTaker

The dataTaker is able to power sensors, relays, etc. from a regulated 5 Volt DC power supply terminal.

In the dataTaker 50 the 5 Volt sensor power supply terminal is located beside analog input channel 5, and is labelled +5V sw.

In the dataTaker 500/600 series loggers the 5 Volt sensor power supply terminal is located near the memory card socket, and is labelled +5V sw.

This power supply can source a current of up to 100 mA.

Caution :  If more than 100 mA current is drawn from the 5 Volt sensor power supply terminal, then the performance of the dataTaker will be affected.

The 5 Volt sensor power supply is automatically switched OFF when the dataTaker drops to the low power or sleep mode.

The 5 Volt sensor power supply is automatically switched ON when the dataTaker is in the normal power or wake mode.

If the 5 Volt sensor power supply is used to power sensors when the dataTaker is powered by the internal battery, then battery life will be reduced.

The circuit schematic for the dataTaker 5 Volt switched power supply is illustrated below

 

 

Figure 10 ñ dataTaker 5 Volt Switched Sensor Power Supply

 

Powering Sensors

The sensor(s) to be powered from the 5 Volt sensor power supply are connected between the +5V sw screw terminal and any GND screw terminal.

The sensors are powered down whenever the dataTaker drops to the low power or sleep mode, and are powered up when the dataTaker wakes and powers up to the normal power mode.

If sensors powered from the 5 Volt sensor power supply have long warm up times, then a warm up delay can be introduced between the switching of the 5 Volt sensor power supply and the commencement of scanning of the sensors.

The dataTaker normally pauses briefly between waking, at which time the 5 Volt sensor power supply is switched ON, and commencing to scan the input channels. This wake delay can also be used to provide time for sensors to warm up.

This wake delay is defined to the dataTaker by the Parameter16 command in the range of 1 to 255 (See Section III ñ Parameter Commands). Parameter16 is specified in increments of 100's of mS.

 

Using DeTransfer, the command for example

P16=30

sets the wake up delay to 3000 mS or 3 seconds.

The wake up delay can be set in the range of 100 to 25,500 mS or 0.1 to 25.5 seconds. The default wake up delay is 100 mS.

The currently defined wake up delay can be determined by the command

P16

Powering Relays

Small 5 Volt relays can be powered directly by the dataTaker, using the 5 Volt sensor power supply.

The relay coil is connected between the +5V sw screw terminal and the digital output channel being used to control the relay.

Page Content


Home

Title and Waranty

Go to: Section 2 | Section 3

Section 1


Construction of the dataTaker 50

Construction of the dataTaker 500 600

Construction of the CEM

Getting Started

 

Section 2


Interfacing

Powering the dataTaker

Powering Sensors from the dataTaker

The Serial Interfaces

The RS232 COMMS Serial Interface

The NETWORK Interface

Analog Process

Connect Analog

Analog Chns

Measuring Low Level Voltages

Measuring High Level Voltages

Measuring Currents

Measuring 4-20mA Current Loops

Measuring Resistance

Measuring Frequency and Period

Measuring Analog Logic State

Measuring Temperature

Measuring Temperature with Thermocouples

Measuring Temperature with RTDs

Measuring Temperature with IC Temperature Sensors

Measuring Temperature with Thermistors

Measuring Bridges and Strain Gauges

Measuring Vibrating Wire Strain Gauges

The Digital Input Channels

Monitoring Digital State

The Low Speed Counters

The Phase Encoder Counter

The High Speed Counters

The Digital Output Channels

The Channel Expansion Module

Installing The Panel Mount Display

 

Section 3


Programming the dataTaker

Communication Protocols and Commands

Entering Commands and Programs

Format of Returned Data

Specifying Channels

The Analog Input Channels

The Digital Input Channels

The Counter Channels

The Digital Output Channels

The Real Time Clock

The Internal Channels

Channel Options

Schedules

Alarms

Scaling Data - Polynomials, Spans and Functions

CVs Calcs and Histogram

Logging Data to Memory

Programming from Memory Cards

STATUS RESET TEST

Switches and Parameters

Networking

Writing Programs

Keypad and Display

Error Mess Text

Appendix A - ASCII

Appendix B - ADC Timing