Q: Can I connect the output of my 4-20mA transducers to these loggers?
A: Yes, you can. Just connect it to the 0-25mA channel of the logger.
Q: What is the accuracy of this logger?
A: The accuracy is +/-1% of full scale for the SR7 and +/-0.5% of full scale for the SRP7 logger.
As an example, the accuracy of the 0-25 mA channel on SR7 is ±0.25mA and that of the SRP7 is 0.125 mA.
Q: Can I measure 20 VDC with this logger?
A: Yes, you can. However, you should add an external resistor. That is, external circuitry is required.
Q: Can I order another combination of the channels, for example I would like 3 channels 0-25ma and the rest 0-5 VDC?
A: Yes, you can. However, as it will be a custom logger there will be an extra cost.
Q: Can an EH-020A probe be used with SR7 or SRP7 loggers?
A: No. The EH-020A (relative humidity and temperature probe) cannot be used with these loggers. It can only be used with SR2 and SRP2 loggers. We do not have any relative humidity sensors for use with SR7 or SRP7.
Q: What is the grounding problem and how can it be prevented?
A: The SRP7 has four common inputs (labeled "Common"). These are not isolated from each other and can be used as the negative "-" connection for the power supply (or battery) and any of the transducers being logged by the SRP7. These common channels are all connected internally.
A grounding loop can occur when there is more than one path to ground in your logger-transducer circuit. Ground loops can damage your SRP7 as well as your transducers. To avoid ground-loop problems in your SRP7 or SR7 circuit:
- Do not use more than one grounded power supply to excite your transducers.
- Do not connect your logger to your computer for realtime readings unless your computer is battery-operated (i.e. not grounded) or your transducer power supply is not grounded.
- If you must use more than one grounded power supply in your SRP7 or SR7 circuit, each transducer you use must be isolated.
- If you must use non-isolated transducers, then you must use a Signal Repeater/Loop Isolator between the transducer output and the SR7 or SRP7.
Q: Can the Rochester Scientific Transducers supplied by ACR be used with the 0-5 Volt channel of the SR7?
A: No. Due to the lower input impedance of our SR7 logger, these transducers should not be used with this logger.