More datapoints, faster scan time. Would be nice if the price were lower, each unit and license is fairly expensive, well worth it, but hard to justify to accounting. Since our last purchase they have added lots more features that we haven't yet explored, so I wouldn't classify myself as an expert on their systems, but I absolutely love the ones we have at this point in time.
Wireless or GSM transmission, Low power consumption, Power backup, Intelligent central server software for controlling a number of loggers remotely, Enable activation of circuits through relays or active electronics.
Scalable, low power consumption, TCP/IP enabled, flexible programmability. Multiple counter and analog inputs, sampling rates up to 1/30 second, SD or other removable card for memory and program files
24 bits / 256 KS/s / Wireless communication to PC / Flexible software suit for Data Logging, sequencing, timing, Easy to set-up ATE, Automatic Test Equipment/
Accuracy API for s/w integration, flexibility, s/w application, option for wireless connectivity, ease of calibration, support multi channel (cost effective through one main frame and multiple sensors), robust mechanical construction, robust electronic construction (ESD, power surge, battery replacement cabinet).
Low cost handheld (built-in sensing device), direct reading/display to pc monitor via usb. Like plug and play type which can be used and operated even by primary students.
Bluetooth communication, 100K 16bit registers, Configuration and Download software in the most common platforms (Iphone, Palm, Windows mobile)
16 / 32 Channel, 16 bit, Modular patch pad, Ethernet (Preferably Wireless Comm), Battery powered / Intrinsically safe
Sounder front end design that allows faster use of the product, for even the most computer illiterate.
A selection of scalable wireless transducers to interface with a datalogger.
A lot data space, connectivity, maybe wireless, low power consumption, remote access.
To be smaller in size and more heat resistant, with less requirement of insulation.
Increasing accuracy, a great capacity of data storage, software as friendly as possible
Flexibility. Types of inputs, sampling rates and anti-aliasing filtering.
Flexibility on channel inputs - universal inputs wireless communication
Accuracy, Sampling speed, Storage mem, Soft for data process
More user friendly and more specialised software
High capacity, stand alone software, remote access
Ease of use, connectivity options, power constraints
Wireless data transmission with multi-channel.
Cheap, easy and modular characteristics
Small size, Very light, Large autonomy
Cheap, simple, fast usable
If you have more than one system that's being monitored, be sure to get the files synchronized. Our systems run on different PC's and the PC times aren't synchronized; This can lead to some false assumptions if you don't take that into account.
Check software and the ability to integrate the hardware with homemade software, Check simultaneous data view and the ability to download while system is still logging, Check idiot proof operation, Check if external power is used, that the data logger moves to battery when power fails. Long life battery.
DO NOT USE DATALOGGERS FOR CLOSED LOOP CONTROL. ONLY DATA CAPTURE. DO USE TO CONTROL ANY SAFETY SYSTEMS. Once you have identified a need for closed loop control then install an engineer system dedicated just for that process. SAFETY FIRST.
Make sure events you want to measure are within the sensitivity and memory capabilities of device. For example, if you are looking for events on a circuit and you size the CT for full load, you will miss the events on a low loaded circuit.
DMM should have the dynamic range and flexibility to handle your weakest and strongest signals. AC & DC. Maybe timing and frequency too. Built-in programmable current-source is needed when using 4 point resistance testing.
The easier to work with. When you are in the field, you must be quick setting it. If it's complicated to set, you are going to fail setting it. Bad weather, no light available, etc, all work together against you.
Check the place where you are going to use it, it's not the same the field, inside a lab, near sea.
if they run on batteries, make sure you monitor the power levels. Nothing's more frustrating than wanting to see some data only to find out the battery failed.
Get ones with a display. Better for set up and evaluation. Stay away from wireless. Most apps don't need it.
Buy data loggers with 10% extra channels
Get enough memory or be upgradable
Need to be web based