Fluke 8846A - Dual Functions; Reading Rates; Ranges

8845A/8846A
Programmers Manual
86
Dual Functions
In addition to the non-compatible functions, there are numerous dual display functions
that are not part of the 884XA meter’s capabilities. Table 34 is a matrix that indicates the
Fluke 45 dual functions and whether or not they are compatible with the Meter.
Table 34. Fluke 45 Dual Function Compatibility Matrix
Secondary Function
Primary
Functions
VDC VAC IDC IAC FREQ OHMS DIODE Period RTD
VDC No Yes No No No No No No No
VAC Yes No No No Yes No No No No
IDC No No No Yes No No No No No
IAC No No Yes No Yes No No No No
FREQ No No No No No No No Yes No
OHMS No No No No No No No No Yes
DIODE No No No No No No No No No
Continity No No No No Yes No No No No
Reading Rates
Like the 884XA meters, the Fluke 45 has multiple but different reading rates. The 884XA
meters reading rates are based on the Number of Power Line Cycles (NPLC), which are
explained in the Users Manual. The Fluke 45, on the other hand, has just three reading
rates, selected as Fast, Medium, and Slow. To be compatible with Fluke 45 code, the
884XA meters will use a reading rate of 2.5, 5, and 20 readings per second, respectively.
Ranges
The Fluke 45 changes range at different points than the 884XA. For example, the 884XA
dc voltage range changes at 100 mV, 1 V, 10 V, and 100 V. The Fluke 45 on the other
hand, changes ranges at the same points when it is in Slow resolution, but for Medium
and High resolution, changes occur at 300 mV, 3 V, 30 V, and 300 V.
The 884XA meters will respond to a range query with the expected Fluke 45 range
whenever the range has previously been set by a range set command. However, when the
884XA meters are set to VDC, VAC or OHMS with autorange enabled and measuring
with Medium or High resolution, the range returned to a range query command may
return a range value that is higher or lower by one range.
For the frequency function, the 884XA meters have one range: 3 Hz. The Fluke 45 has
five ranges. If the 884XA meters are set a range set command, they will respond to a
range query with the set range value. If, however, the frequency function is in autorange,
the 884XA meters will respond with the value of zero.
The Fluke 45 allows range selection in CONTINUITY and DIODE TEST. The 884XA
meters have only one range for these functions. Therefore, whenever a RANGE
command is detected in the Fluke 45 emulation mode, the 884XA meters will respond
with an error.