Temperature data loggers: Fluke 53/54 versus Omega HH147
I've been using an OMEGA HH147 now for about 5 months with an 'Eric-s' group head thermocouple port adapter.
Unfortunately I don't have direct hands on experience with the Fluke so I'm limited in what I can say about the Fluke 53/54 although my experience with Fluke electronics test equipment is: Fluke instruments are very good quality. (My personal Multimeter is a Fluke but I can rationalize this because I sometimes do contract EE work).
The accuracy specifications for the Fluke 54 are better than the Omega HH147:
Fluke 53/54 series II: ±[0.05% + 0.3°C]
Translated: At 100°C then +/- 0.35°C = +/-0.63°F
Omega HH147: ±(0.1% rdg + 0.7°C)
Translated: At 100°C then +/- 0.8°C = +/-1.44°F
I'm not as concerned about accuracy (It's easy to calibrate, just measure the temperature of boiling water compensated for elevation.) as much as precision (consistency in measurement), noise, the sampling rate, the amount of data that can be logged, the software for the PC and the overall cost. Also, I've used three channels at once (group head, HX top, HX bottom) so having the four channel Omega HH147 is actually useful .
The noise level in my temperature data from the Omega HH147 is normally about 0.33°F peak to peak. To get the noise level down to this level required careful selection of the thermocouple and fitting a ferrite bead on the thermocouple leads.
The maximum sampling rate for both the Fluke and Omega units is 1 second which I think is only marginally fast enough. I would like to see two samples per second...
The amount of data that can be logged by the stand alone Fluke 53/54 is limited to 500 samples (at one sample per second this means 8.33 minutes) while the Omega HH147 standalone limit is 10,000 samples of all 4 channels (at one sample per second this means 2.78 hours). I presume unlimited recording is available with the PC attached for the Fluke 53/54 like it is for the Omega HH147. With the HH147, a little care needs to be taken with grounding considerations when connecting the PC to the data logger. I use ungrounded thermocouples to eliminate this problem.
The HH147 includes M$ Windows software to download and display the downloaded data and it is integrated with M$ Excel to provide rather easy data analysis and viewing. The Omega software is not perfect and but it is functional.
The Fluke models 53/54 do not include software and it's an expensive addition.
The communications interface for HH147 is RS232 which is not so common today as it once was. I don't know of any PCs sold new today with an integrated RS232 port. The way around the dilemma is to purchase a USB to RS232 port adapter. I have used both Prolific and FTDI USB to RS232 port adapters and have found that the FTDI units are more reliable than the Prolific units. The Prolific units have given me more than my share of problems. The USBGEAR (USBG-RS232-F12) product works better with the Omega HH147 than either of my Prolific USB to RS232 port adapters.
Both the Fluke and Omega have elapsed time displays which are really useful to me with my HX machine for tracking the time between the water dance and when I start the extraction.
The battery life for the HH147 is 550 hours while the fluke 53/54 have battery life specifications of 1000 hours.
I predict the Fluke 53/54 is a better product than the Omega HH147 but the 'better' comes at a price.
Prices as of March 2009
Fluke 53-2 (one channel) (54-2 60HZ): $272.00
Fluke 54-2 (two channel) (53-2 60HZ): $313.65
Fluke software (FVF-SC1): $176.86
Omega HH147 (4 channel): $299.00
FTDI USB to RS232 port adapter(USBG-RS232-F12): $19.99