Datasheet

71M6543F/71M6543G Data Sheet
124 v2
1Wh/pulse, a power applied to the meter of 120 V and 30 A results in one pulse per second. If the load is
240 V at 150 A, ten pulses per second are generated.
Control is transferred to the MPU for pulse generation if EXT_PULSE = 1 (CE RAM 0x20[5]). In this case,
the pulse rate is determined by APULSEW and APULSER (CE RAM 0x45 and 0x49). The MPU has to load
the source for pulse generation in APULSEW and APULSER to generate pulses. Irrespective of the
EXT_PULSE status, the output pulse rate controlled by APULSEW and APULSER is implemented by the CE
only. By setting EXT_PULSE = 1, the MPU is providing the source for pulse generation. If EXT_PULSE is 0,
W0SUM_X and VAR0SUM_X are the default pulse generation sources. In this case, creep cannot be
controlled since it is an MPU function.
The maximum pulse rate is 3*F
S
= 7.5 kHz.
See 2.3.6.2 VPULSE and WPULSE (page 27) for details on how to adjust the timing of the output pulses.
The maximum time jitter is 1/6 of the multiplexer cycle period (nominally 67 µs) and is independent of the
number of pulses measured. Thus, if the pulse generator is monitored for one second, the peak jitter is
67 ppm. After 10 seconds, the peak jitter is 6.7 ppm. The average jitter is always zero. If it is attempted
to drive either pulse generator faster than its maximum rate, it simply outputs at its maximum rate without
exhibiting any rollover characteristics. The actual pulse rate, using WSUM as an example, is:
Hz
XFWSUMWRATE
RATE
S
46
2
⋅⋅⋅
=
,
where F
S
= sampling frequency (2184.53 Hz), X = Pulse speed factor derived from the CE variables
PULSE_SLOW (CE RAM 0x20[0]) and PULSE_FAST (CE RAM 0x20[1]).