The Analog Input ChannelsThe dataTaker analog input channels are used for measuring a large variety of analog signals from sensors, transducers, instruments, etc. The dataTaker models have a different number of analog input channels as follows dataTaker 50 5 differential, 10 single ended analog channels The dataTakers and the Channel Expansion Modules also have several internal analog channels, which are used for monitoring calibration references, and case temperature. These channels are not available for measurement of external signals, but can be read in the same manner as the analog input channels. The allocation of analog input channels for each of the models of the dataTaker and the Channel Expansion Module are summarised in the sections below. Analog Channels of the dataTaker 50The dataTaker 50 has 7 analog input channels, which are allocated between external user channels and internal reference channels as follows Channels 1 to 5 ñ user analog input channels Channel 1% ñ dataTaker 50 case temperature Channel 2% ñ zero voltage, and 100.0 Ohm resistance reference Analog Channels of the dataTaker 500/600 SeriesThe dataTaker 500/600 series loggers have 12 analog input channels, which are allocated between external user channels and internal reference channels as follows Channels 1 to 10 ñ user analog input channels Channel 1% ñ dataTaker 500/600 case temperature Channel 2% ñ Internal zero voltage, and 100.0 Ohm resistance reference Analog Channels of the Channel Expansion ModulesThe Channel Expansion Module (CEM-AD) has 12 analog input channels which are allocated as follows Channels n:1 to 10 ñ user analog input channels Channel n:1% ñ CEM case temperature Channel n:2% ñ internal zero voltage where n is the Channel Expansion Module number. The analog input channels of the Channel Expansion Module are implemented in same way as those of the dataTaker. Differential and Single Ended Analog InputsThe analog input channels of the dataTaker and Channel Expansion Modules can be used for measuring differential inputs and single ended inputs. The differential and single ended input modes can be mixed within an application. Details for connecting analog signals as differential inputs and as single ended inputs are given in Section II. Differential Analog InputsDifferential inputs are applied between the positive terminal and the negative terminal of each of the analog input channels. The dataTaker 50 can accept up to 5 differential inputs, while the dataTaker 500/600 series can accept up to 10 differential inputs. Details for connecting analog signals as differential inputs are given in Section II. Differential analog inputs are specified by nominating the channel number and signal type as the following examples illustrate 3V voltage between + and - terminals of channel 3 Using DeTransfer, differential analog inputs are specified if the channel number has no analog terminal specified, as shown in the examples 3V Using DeLogger, differential analog inputs are selected from the dialog which opens for the selected signal or sensor group, for example
Single Ended Analog InputsSingle ended inputs are applied to the analog input channels in several different configurations between the positive terminal + and Analog Return terminal R between the positive terminal + and the SE REF terminal between the negative terminal ñ and Analog Return terminal R between the negative terminal ñ and the SE REF terminal between the Excite terminal T and the Analog Return terminal R or the SE REF terminal. This mode is not appropriate for resistance or RTD inputs, and is not available in the dataTaker 50 between the Analog Return terminal R and any Ground terminal G for current, current loop and AD590 types only The single ended inputs between the +ve, ñve or T terminals and the SE REF terminal are actually measured differentially by the dataTaker. However, these input configurations are referred to as single ended input modes, as distinct from the true differential input mode. Single ended analog inputs are specified by nominating the channel number and the terminal for the positive lead of the signal, and the signal type as the following examples illustrate 3+V voltage between + and R terminals of channel 3 Using DeTransfer, single ended analog inputs are specified if the channel number includes an analog terminal which is the nominal positive side of the signal, as shown in the examples 3+V Using DeLogger, single ended analog inputs are selected from the dialog, which opens for the selected signal or sensor group, for example
Single Ended Inputs for the dataTaker 50These single ended analog input arrangements provide a for a total number of single ended channels for the dataTaker 50 as follows 15 single ended input channels for measuring current, 4-20 mA current loop and AD590 temperature sensors 10 single ended input channels for measuring resistance and RTDs 10 single ended input channels for measuring all other analog signal and sensor types. Details for connecting analog signals to the dataTaker 50 as single ended inputs are given throughout Section II. Single Ended Inputs for the dataTaker 500/600 SeriesThese single ended input arrangements provide a total number of single ended channels for the dataTaker 500/600 series loggers as follows 40 single ended input channels for measuring current, 4-20 mA current loop and AD590 temperature sensors 20 single ended input channels for measuring resistance and RTDs 30 single ended input channels for measuring all other analog signal and sensor types. Details for connecting analog signals to dataTaker 500/600 series loggers as single ended inputs are given throughout Section II. Analog Input TypesThe different types of analog signals and sensors that are supported by the dataTaker are described in detail in Section II of this manual. Each of the signals and sensors supported are specified in schedule lists using input signal type or sensor type identifiers. These type identifiers generally are abbreviations of the actual signal or sensor name. The type identifiers, channel capacity, connection configurations, default channel options and other details for the various analog signal and sensor types supported by the dataTaker are detailed in the table overleaf.
Analog Input Types
Reading Differential Analog ChannelsThe dataTaker 50 has 5 differential analog input channels, and the dataTaker 500/600 series loggers have 10 differential analog input channels. These analog input channels are used as differential channels to differentially measure analog signals. In the differential input mode, the input signals are connected between the positive (+) terminal and the negative (ñ) terminal of each channel (See Section II ñ Differential Analog Input Mode). Specifying Differential ChannelsDifferential analog input channels are specified by the general format ntype(options) and n..mtype(options) where n is a single differential analog channel If the analog channels are located on a Channel Expansion Module, then the module number precedes the channel number(s). Some examples of specifying differential analog input channels using DeTransfer are given below BEGIN which returns data for the channels every 5 minutes as follows the voltage input to channel 1, multiplied by an attenuation factor of 2.5 the 4 - 20mA current loop input to channel 2 across an external 120 Ohm shunt the temperature from three type K thermocouples input to channels 3, 4 and 5 the resistance input to channel 10 by a 4 wire configuration the frequency input to channel 8 In DeLogger, differential channels are specified for reading in the Program Builder by selecting the channel number and channel types descriptively from the walking menus and dialog boxes. For example Reading Single Ended Analog ChannelsThe analog input channels of the dataTaker can also be used for single ended inputs, to measure analog signals that are referenced to a common point. The dataTaker 50 supports 10 single ended analog inputs (two per physical analog channel), while the dataTaker 500/600 series loggers support 30 single ended analog inputs (three per physical analog channel). In the single ended input mode, the input signals are applied to the analog input channels in a number of ways (See Section II - Single Ended Analog Input Mode). The single ended measurements can be referenced to the dataTaker ground, to an external ground different to dataTaker ground, or to a 2.5 Volt reference within the dataTaker. Single Ended Inputs Referenced to dataTaker GroundSingle ended analog inputs which are to be measured with reference to dataTaker ground are connected to analog channels as follows between the positive terminal + and Analog Return terminal R between the negative terminal ñ and Analog Return terminal R between the Excite terminal T and Analog Return terminal R. This mode is not suitable for resistance or RTD inputs, and is only available in the dataTaker 500/600 series loggers between the Analog Return terminal R and any Ground terminal G for current, current loop and AD590 temperature sensors only Single Ended Inputs Referenced to anExternal GroundSingle ended analog inputs that are to be measured with reference to an external ground are connected to analog channels as follows between the positive terminal + and the SE REF terminal between the negative terminal ñ and the SE REF terminal between the Excite terminal T and the SE REF terminal. This mode is not suitable for resistance, RTD or thermistor inputs, and is only available in the dataTaker 500/600 series loggers. The Number of Single Ended InputsThe single ended configurations provide for the following number of single ended channels in the dataTaker 50 15 single ended analog input channels for current, current loop and AD590 measurements 10 single ended analog input channels for all other analog signal measurements. The single ended configurations provide for the following number of single ended channels in the dataTaker 500/600 series loggers 40 single ended analog input channels for current, current loop and AD590 temperature sensor measurements 30 single ended analog input channels for all other analog signal measurements. Single ended input channels cannot be used for some analog input types such as 4 wire resistances, 4 wire RTDs, current excited bridges, etc. as detailed in the table of Analog Input Types above. Specifying Single Ended ChannelsWhen single ended inputs are measured with reference to the Analog Return terminal, the input mode is specified by suffixing the following special characters to the channel number T for Excite terminal single ended inputs
The general formats of commands for specifying single ended analog inputs referenced to Analog Return follow nTtype The dataTaker 50 does not support the excite terminal as an input terminal. The positive side of the signal is connected to these terminals, and the negative side is connected to the reference (Analog Return or SE REF). The commands detailed below configure the channel inputs internally for the correct polarity. Specifying Sequences of Single Ended ChannelsThe general format for specifying sequences of single ended analog inputs referenced to Analog Return follows nT..mTtype nT..m+type nT..mñtype where n is a single ended analog channel If the analog channels are located on a Channel Expansion Module, then the module number precedes the channel number(s). When sequences of single ended inputs are specified in these formats, then the actual sequence of successive single ended input channels is interpreted as follows if the single ended channel sequence is specified in terms of the +ve and ñve terminals only, the sequence is interpreted as successive +ve and –ve terminals. For example 1+..3ñ interprets as 1+ 1ñ 2+ 2ñ 3+ 3ñ if the single ended channel sequence is specified in terms of the T terminal and either the +ve or the ñve terminal, then the sequence is interpreted as successive T, +ve and ñve terminals. For example 3T..4ñ interprets as 3T 3+ 3ñ 4T 4+ 4ñ if the single ended channel sequence is specified in terms of the Analog Return # terminal, then the sequence is interpreted as successive Analog Return # terminals. For example 1#..4# interprets as 1# 2# 3# 4# Some examples of specifying single ended analog input channels referenced to the Analog Return (R) using DeTransfer are given below RA1H 3+V 5-V returns data every hour for the single ended voltage input connected between channel 3+ and R, and the single ended voltage connected between channel 5ñ and R. R5S 1*..2ñTK returns data every 5 seconds for the six single ended thermocouples inputs connected between channels 1T and R, 1+ and R, 1ñ and R, 2T and R, 2+ and R, 2ñ and R. R1M 3+..4+F returns data every minute for the three single ended frequency inputs connected between channels 3+ and R, 3ñ and R, 4+ and R. In DeLogger, single ended channels referenced to Analog Return (R) are specified for reading in the Program Builder by selecting the channel number and channel types descriptively from the walking menus and dialog boxes. Single Ended Inputs Referenced to an External CommonWhen single ended inputs have a common external ground point which is different to dataTaker ground, then these can be measured with respect to that external ground by connecting the ground to the SE REF terminal. Measurements made with respect to this external ground are actually made differentially between the input terminal and SE REF. This reference to the external common rather than to dataTaker ground is specified by the X (eXternal ground) channel option channel(X) The general format for specifying externally referenced single ended analog inputs is the same as that described above for single ended analog inputs referenced to Analog Return. Some examples of specifying single ended analog input channels referenced to an external ground connected to SE REF using DeTransfer are given below R2H 5+V(X) 6-LM35(X) returns data every 2 hours for a single ended voltage input between channel 5+ and SE REF, and a single ended LM35 input between channel 6ñ and SE REF. R1M 4+..5*V(X) returns data every minute for the three single ended voltage inputs between channels 4+, 4ñ, 5T, and SE REF R10S 3*..4ñTK(X) returns data every 10 seconds for the six single ended thermocouples connected between channels 3T, 3+, 3ñ, 4T, 4+, 4ñ and SE REF. In DeLogger, single ended channels referenced to an external grounds are specified for reading in the Program Builder by selecting the channel number and channel types descriptively from the walking menus and dialog boxes. Combining Input ModesSchedule lists can include a mix of differential and single ended channels, and a mix of single ended references. The list can also include a mix of single channels and channel sequences. An example of a channel list which includes both differential and single ended analog channels is given below R1D 1+..6-V(X) 7R 8TN 9+F 10*..10ñLM34 Reading the Same Channel for a Number of InputsEach analog input channel of the dataTaker data loggers can be read for any number of different analog input types if required. 3V 3+V 3-V 3TJ which will return the differential voltage output by the thermocouple in response to temperature the offset voltage or common mode voltage for each side of the thermocouple, with respect to dataTaker ground the temperature sensed by the thermocouple |
Page ContentSection 1Construction of the dataTaker 50 Construction of the dataTaker 500 600
Section 2Powering Sensors from the dataTaker The RS232 COMMS Serial Interface Measuring 4-20mA Current Loops Measuring Frequency and Period 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 Installing The Panel Mount Display
Section 3Communication Protocols and Commands Entering Commands and Programs |
