T24 Radio Telemetry

FAQs > T24 Radio Telemetry

Welcome to the T24 Knowledge Centre

Here we aim to answer your questions about the design and function of the T24 radio telemetery system, please scroll down the page to see a range questions and answers.

If you have any further queries, please do not hesitate to contact us using the 'Need Help' links on the left panel.

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T24 General FAQ's:

Q: What is the range of T24?

A: The T24-ACMm which has an integral antenna has a range of 100 metres direct line of sight. The T24-ACM / T24-ACMi uses a integrated PCB T24-ANTA antenna provides up to 200 metres range in ideal conditions. This range can be doubled using the T24-AR (Active repeater).

Q: What inputs are available to the T24 system?

A: The T24 system supports Strain, Current, Voltage, Temperature, Pulse and Potentiometer acquisition.

Q: How reliable are the readings?

A: Due to the digital nature of the T24 system, when a reading is received by any device it is guaranteed not have been distorted over the RF transmission.

Q: What software is provided with the T24 devices?

A: All devices are supported by the T24 Tool Kit which allows users to
configure all devices from the T24 range as well as view and log data from
acquisition modules in range. The software can also be downloaded directly
from our website.
 

Q: How many devices can operate on one radio channel?

A: Many devices can operate on the same radio channel depending on the sample rate of the acquisition modules present in the system. There are 16 channels available with each one capable of supporting up to 200 data packets per second.

Q: Can PC software gather data from many devices?

A: Yes, Mantracourt provides freeware for logging up to 24 inputs to one base station, in addition the open COM driver can be used to gather data through customers own PC software to applications in Visual Basic which in turn has been used to integrate the T24 system with Lab View.

Q: What limits the RF range of the devices?

A: Any metal surface will reflect 2.4 GHz radio waves, therefore in a sealed metal box, no RF will escape. However by providing a suitable RF window the signals will propagate out.

Q: What Frequency does the system operate on?

A: Licence free world wide 2.4GHz, although this frequency is used by other equipment the T24 range has been tested with Bluetooth, Zigbee & WiFi devices with out conflicts.

Q: Is it possible to use repeaters within T24 network?

A: The T24-AR Active repeater which can be added to the system can propagate a signal around corners and obstacles. This unit can also double the effective range.

Q: Is the system point to point?

A: Yes, however the modules may also operate in many to one (such as multiple data acquisition modules communicating with a base station) and one to many (such as a data acquisition module supplying data to multiple handhelds and displays).

Q: What sensors would these inputs cover?

A: Any sensor that provides a voltage, current or ratio metric interface can be connected to an acquisition module, including load cells, inclinometers, accelerometers, displacement LVDT, pressure, potentiometer, pulse, temperature, humidity, ph, shock.

Q: What is the communication protocol?

A: Proprietary protocol based on a 804.15.4 chip. This allows the T24 range to co-exist with Bluetooth, Zigbee & WiFi devices with out conflicts.

T24 Acquisition Module FAQ's:

Q: What are the sampling rates of the acquisition modules?

A: The T24 standard acquisition modules (SA, IA, VA, RA, TA, PA) sample from 0-200 updates/sec. The T24-SA fast acquisition modules are fixed at 2,000 updates/sec.

Q: What is the resolution of the acquisition modules?

A: The noise free resolution for a sample time of 10 milli-seconds or less is 15.5 bits for the T24 SA, 12.5 bits for the T24-VA, 14 bits for the VA and 12.25 bits for the T24IA.

The T24-PA’s accuracy % input error @ 1 Hz is 0.15% and for the T24 RA the accuracy is 0.01% of the full scale.

With increased sample times resolution can be increased up to 18.75 bits for the T24-SA.
 

Q: What is the supply voltage for the acquisition modules?

A: 3V for the acquisition modules and handheld displays. Other modules in the range take 9-36 V.

Q: How are the modules powered?

A: Two standard AA batteries or the T24-BC1 Battery Charger, which provides a re-chargeable power supply using a Li-ion Cell. Find out the battery life of your system using our Battery Calculator.

Q: Can power be provided to a sensor?

A: Yes, all acquisition modules feature a 5V supply which is a excitation voltage (with exception of T24-RA which has 2.5V supply).

Q: How is the strain gauge acquisition module calibrated?

A: The modules are factory calibrated to 2.5 mV/V which can be custom calibrated and linearised over up to 9 points by using the T24 Toolkit. The T24-SAf has fixed factory calibration and cannot be linearised.

Q: What is the difference between the ‘i’ and ‘e’ versions of the acquisition units?

A: The ‘i’ modules all feature an on chip integrated antenna. The ‘e’ modules are fitted with a miniature UFL connector which can be used with any of the antenna options available; the T24-ANTA (PCB antenna) or T24-ANTB (fixed 90 degree Whip antenna) or T24-ANTC (flexible whip antenna).

Q: What is the difference between the T24-SA and T24-SAf?

A: The standard acquisition modules are capable of providing data up to 200Hz. The ‘fast’ T24-SAf provides data at a fixed 2Khz.

Q: How do I reset the counter value?

A: The counter value can be reset either by contacting the digital input to the ground or by transmitting a data packet with a defined data tag from another device, such as a T24-HA, T24-RM1 or even another T24 acquisition module.

Q: What is the counter, and its maximum value?

A: The counter is a counter which increments every time a pulse is detected either on rising or falling edge which can be set in the tool kit. When counting pulses the sample time and transmit intervals must be set to the same value. Low power cannot be used to ensure the input is constantly sampled. The maximum value for the counter is 4,294,967,295 at which point the counter will overflow.

Q: How do I calibrate the output?

A: The device is factory calibrated to the nearest 0.25 μS which provides users with a set of predefined outputs; Hz, RPM and Period. All of these values can have a custom gain and offset applied to them, the resulting output can therefore be in whatever units or range of values you require.

Q: How accurate is the measurement?

A: The worst case accuracy is stated as 0.25% at the top end of the input range i.e. 3 kHz. Just under half this error is to allow for temperature drift over the full operating temperature range of the device (-40 to +85 degrees) so the accuracy in a stable temperature environment is far less. At slower input rates (down to 1Hz) the accuracy increases further down to 0.15% where 0.1% allows for temperature drift.

Q: What types of inputs can be used?

A: Any volt free contact input such as relays, voltage sources (up to 24 volts) and NPN open collector inputs.

Q: Can I use a rotary input?

A: The T24-RA is designed to work with potentiometer inputs that pass from 0-100%. To avoid the T24-RA providing numbers that are outside the calibrated output the module has a rotary limit. This is the value at which the input is expected to move between the maximum and minimum values.

Q: Can I just measure a resistance?

A: The T24-RA is a potentiometer input which means it can not measure resistance directly yet if wired into a potential divider circuit, with a known resistor value, the change in resistance can be measured.

Q: How do I calibrate the device?

A: The module has a 9 point linearization and calibration feature which allows users to calibrate the percentage output into whatever units are required. For example, calibrating a linear potentiometer would be performed by entering the distances that the plunger you want to measure moves and calibrating at 9 points over that range.

Q: What output does the device provide?

A: The T24-RA is factory fitted and calibrated to provide an output between 0-100% as the input value varies between the negative and positive excitation.

Q: Can I just measure a resistance?

A: The T24-RA is a potentiometer input which means it can not measure resistance directly yet if wired into a potential divider circuit, with a known resistor value, t

Q: How can I account for long cable length when performing two wire measurements?

A: There is a custom offset that can be used. This can be used to offset a temperature inaccuracy due to long cable lengths when using two or three wire connections.

Q: Is there a way to apply a custom calibration?

A: There is no custom calibration on this device however an offset can be applied to any outputted values.

 

Q: What units are available?

A: The T24-TA can output values in degrees Celsius, degrees Fahrenheit, Kelvin or Ohms.

Q: What type of sensor can I use with this device?

A: The T24-TA module is factory calibrated to work with PT100 (Type 385) sensors which have a defined change in resistance per degree. (DIN 43760)

Q: What wiring configurations are available?

A: The T24-TA can be wired in 2, 3 and 4 wire configurations; users are able to choose the best option for their application depending on accuracy requirements, cost and distance between acquisition module and probe.

Q: What are the input ranges of the T24 acquisition modules?

A: T24-SA 2.5mV/V calibrated strain gauge based measurement; T24-VA 0-10V, T24-IA 4-20mA, T24-TA pt100 sensor input, T24-RA potentiometer 500 to 100000 Ohms and T24-PA 0.5Hz to 3kHz.

T24 Base Station FAQ’s:

Q: What is the function of the USB and industrial base stations?

A: Both provide users with a PC interface by which collect data from any acquisition module with in range and configure all devices in the T24 range.

Q: How is the industrial base station different to the USB base station?

A: The industrial base station provides not only USB interface but also RS232 and RS485 at multiple baud rates. This module can also be DIN rail mounted.

Q: How many acquisition modules can be acquired by the base stations?

A: Each base station can use one of 16 channels. From one of those channels a base station can collect data simultaneously from any number acquisition modules depending upon the frequency of readings being provided by the acquisition module.

Q: What is the difference between the T24-SO Serial Output and T24 Base Stations?

A: The T24-SO gathers data from up to 8 acquisition modules and, on its serial output, provides a user configurable ASCII string. The output string can contain the summed value of the gathered data. This output can be used to drive serial displays, printers or to simply feed directly into a PC, PLC or other data acquisition systems.
The base stations communicate bi-directionally so are used to configure the devices as well as gather data. The communications protocol is binary and packet based and so requires processing to present the data to the application in a formatted manner.
 

Q: How many T24 Acquisition modules can be controlled by one USB Base Station at the same time?

A: Acquisition modules are not controlled when providing data, rather data is provided at a user determined rate during configuration set up. The base station can gather data from any number of acquisition modules providing they are on the same channel. The number of modules a single base station can process depends upon the frequency of transmission from the acquisition modules that channel.

Q: Can base stations integrate to other communications protocols?

A: Our SCADA software package ‘Visual Link’ interacts with all of our devices
allowing a PC to enact the conversion. In addition, with the use of the .DLL and
COM driver provided with the T24 Tool Kit, users can create tunnelling between the data provided by the base station to the PC and another communications protocols.
 

Q: Once an acquisition module has been configured, will it require regular connections to the base station?

A: No. Once an acquisition module has been configured it will remain stable for its lifetime providing its operating limits are not exceeded.

T24 Handheld Display FAQ’s:

Q: What is the battery life of the handhelds?

A: 40 hours continuous use.

Q: Are they IP or NEMA rated?

A: Yes to IP65 NEMA4.

Q: What batteries are required?

A: 2 x AA, Alkaline, Zinc or Rechargeable NiCad, NiMH.

Q: What is the difference between the T24-HS, HA & HR handhelds?

A: The T24-HS provides easy one-to-one communication with a single acquisition module.
The T24-HA advanced provides communication with up to 12 acquisition modules providing both individual and resultant values, as well as the ability to transmit data to other output devices using the F1 function key.
The T24-HR roaming will acquire data from any number of acquisition modules in range, offering the most powerful (nearest) one for display first.
 

T24 Accessories FAQ's

T24 Analogue Output FAQ's:

Q: How does an input equate to the output?

A: Using the T24-TK (toolkit software) you can declare the upper and lower limits of an output for a given input.

Q: What Outputs are available?

A: The T24 AO1 (Analogue output) provides 0-10, +/- 10v, 0-5V, +/- 5V 0-20mA 4-20mA source and sink outputs.

Q: How many inputs can a T24-AO1 output?

A; Just one. Although the AO1 has multiple outputs, only one acquisition module can provide data to it.

Q: What is the difference between the T24-AO1 and T24-AO1i?

A: The modules are identical in functionality apart from the T24-AO1i is an IP65 enclosed version where the T24-AO1 is designed for desktop applications rather than industrial.

T24 Acquisition Connectivity Module FAQ's:

Q: What is an ACM?

A: An ACM (acquisition connectivity module) is a housing for any T24 Acquisition module providing IP65 protection, or higher with specialist glands, along with power and easy to use field terminals for connecting sensors.

Q: What is the difference between the ACM and ACMi?

A: The T24-ACMi is physically smaller and provides power via 2 x AA batteries and has smaller terminal block style field connectors for wiring to acquisition modules. The T24-ACM although larger can provide power from an external power supply (5-18V) as well as 2 x D cell batteries which provide a higher battery capacity allowing for longer battery life.

Q: What Acquisition module fits with the ACM and ACMi?

A: When using either ACM you will require an acquisition module that can accept an external antenna denoted by an ‘e’ on the end of the model name. Both ACM’s benefit from being fitted with a T24-ANTA which provides the best omni transmission range although higher gain and more directional antennas such as the T24-ANTC can also be fitted.

T24 Serial Output FAQ's:

Q: What does the serial output provide?

A: The serial output provides an ASCII string output of up to 8 values in a user formatted string.

Q: How can I display data using the T24-SO?

A: By combining the T24-SO with a serial display such as Mantracourt’s SerialDis unit a display can be created that updates as often the acquisition module transmits data.

Add in Relay Modules Q’s, AR, antenna available for the OEM boards
Licensing and approvals?