Both Units are Tested Safe for Use in CAT III 600V Environments and are Otherwise Quite Similar
In terms of Voltage, Current, Resistance, Frequency, and Capacitance measurement, the 115 and 117 are identical. Both are safe for CAT III 600V environments and boast a basic DC accuracy of +/- .5%. The general appearance and weight are also nearly identical, apart from the AutoV/Loz and Volt Alert indicators on the 117.
Neither the 115 or 117 offer Temperature Measurement, Data Logging, or a Lifetime Warranty
For those advanced features check out the Fluke 87-5, 179, or 289 Digital Industrial Multimeters.
View the Fluke 115 ➔ or the Fluke 117 ➔