SA4104A / SA4104B
The Rated Condition Select pins (R0, R1, R2, R3) together
with the FMS pin are used to select different LED output
frequencies which in turn determine the applications meter
constant. Refer to Figure 9 for the LED output timing diagram.
When the FAST mode is enabled the LED output generates
pulses at a nominal frequency of 5kHz at IMAX and VMAX. In
this mode the pulse frequency is proportional to the average
power consumption measured. This mode is useful when
interfacing to a microcontroller.
Table 3 illustrates some of the possible LED and motor
constants that are achievable for some common values of
IMAX using a VNOM between 220V and 240V.
Table 2: LED and motor division factors
FMS
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
R3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
R2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
R1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
R0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
DF_LED DF_MO
220
440
880
1760
220
440
880
1760
220
440
880
1760
220
440
880
1760
1464
2928
352
704
584
1168
352
704
584
1168
352
704
292
584
234
468
256
128
64
32
128
64
32
16
64
32
16
8
When FMS is floating the LED pin outputs fast mode pulses.
The motor pulses occur as usual based on the last FMS
before a floating condition was detected as well as the current
states of R0, R1, R2 and R3. If a floating condition on FMS is
detected at device start-up the motor pulses are generated
based on FMS set to VSS
.
Rated Condition Select (R0, R1, R2, R3)
The Rated Condition Select inputs (R0, R1, R2 and R3) along
with the Fast Mode Select input (FMS) are used for obtaining
a multitude of meter constants and motor drive ratios. The
different LED and motor division factors (DF_LED and
DF_MO) that can be selected via R0, R1, R2, R3 and FMS
are shown Table 2.
32
16
8
4
To calculate the LED output pulse constant in STANDARD
mode and the motor drive pulse constant for any meter rating
(IMAX and VNOM) the following formulae can be used:
64
32
64
32
32
16
32
16
16
8
퐼푉푃 5000 1000 × 3600
퐿퐸퐷 ꢀ푚푝/푘푊ℎ =
×
×
16 퐷퐹ꢉꢊꢋ 푉ꢌ푂푀 × 퐼푀퐴푋
...(1)
where
IMAX is the maximum rated mains current,
VNOM is the nominal mains voltage,
IVP is the analog input current on the voltage sense input at
VNOM as specified in Table 1 and
DF_LED is the dividing factor for the LED output that is set by
the combination of R0, R1, R2, R3 and FMS as specified in
Table 2.
16
8
16
8
Equation 1 is based on the assumption that the input current
into the IIP/IIN current sense input is set to 16μARMS at IMAX
.
16
8
퐿퐸퐷 ꢀ푚푝/푘푊ℎ
ꢇ표푡표푟 ꢀ푚푝/푘푊ℎ =
퐷퐹_ꢇꢍ
1
Note:
Pin values defined as follows
…(2)
0
1
pin is connected to VSS
pin is connected to VDD
where
LED imp/kWh is the LED constant as calculated using
Equation 1 and
DF_MO is the dividing factor for the motor output that is set
by the combination of R0, R1, R2, R3 and FMS as specified
in Table 2.
SPEC-1654 (REV. 4)
29-09-2017
10/18
SAMES [ SAMES ]
