Four Terminal Capacitance Decade

In addition to the seven direct-reading capacitance values, an infinite number of intermediate or higher
capacitance values can be obtained by using external capacitors.
An external capacitor is simply connected to the 1417's external standard terminals,
either directly or in parallel with a 1µF internal standard, and the resulting capacitance is scaled in
value by the 1417's inductive voltage dividers. The direct-reading accuracy of the 1417 is ±0.25% plus
ratio accuracy at test frequencies of 100, 120, or 1000Hz.
Since the 1417 scaling ratios are precise and repeatable, better accuracy can be obtained by measuring the actual value of the internal 1µF standard or of an external standard before scaling.

The 1417 also serves as a standard of dissipation factor (D). The dissipation factor of the 1417 is intentionally set to 0.01 at test frequencies of 100, 120 and 1000Hz. Basic D accuracy at these frequencies is ±0.001. The 1417 may also be used as a two-terminal capacitance standard when
higher D values can be tolerated. In a two-terminal configuration, D is less than 1 for capacitance
values up to 1000µF at frequencies below 150Hz.
This feature allows the 1417 to be used in calibrating the higher capacitance ranges of popular
universal or RLC bridges. One additional feature of importance is that all the 1417's parameters are measurable (without disassembly) so, in effect, its ultimate accuracy depends on the accuracy of
the external measurement equipment.