- 您现在的位置：买卖IC网 > Sheet目录1213 > EVAL-ADE7751ZEB (Analog Devices Inc)BOARD EVALUATION FOR ADE7751
ADE7751
Example 1
Table IV.
If full-scale differential dc voltages of +660 mV and –660 mV are
applied to V1 and V2 respectively (660 mV is the maximum
differential voltage that can be connected to Channel 1 and
Channel 2), the expected output frequency is calculated as follows.
Gain = 1, G0 = G1 = 0
F 1–4 = 1.7 Hz, S0 = S1 = 0
V1 = +660 mV dc = 0.66 V (rms of dc = dc)
V2 = –660 mV dc = 0.66 V (rms of dc = |dc|)
V REF = 2.5 V (nominal reference value)
Note: If the on-chip reference is used, actual output frequencies
may vary from device to device due to reference tolerance of ± 8%.
SCF
1
0
1
0
1
0
1
0
S1
0
0
0
0
1
1
1
1
S0
0
0
1
1
0
0
1
1
F 1–4
(Hz)
1.7
1.7
3.4
3.4
6.8
6.8
13.6
13.6
CF Max for AC Signals
(Hz)
128 × F1, F2 = 43.52
64 × F1, F2 = 21.76
64 × F1, F2 = 43.52
32 × F1, F2 = 21.76
32 × F1, F2 = 43.52
16 × F1, F2 = 21.76
16 × F1, F2 = 43.52
8 × F1, F2 = 21.76
Freq =
5.74 × 0.66 × 0.66 × 1 × 1.7 Hz
2 . 5 2
= 0 . 68 Hz
(8)
SELECTING A FREQUENCY FOR AN ENERGY METER
APPLICATION
Example 2
In this example, if ac voltages of ± 660 mV peak are applied to
V1 and V2, the expected output frequency is calculated as follows.
Gain = 1, G0 = G1 = 0
As shown in Table II, the user can select one of four frequencies.
This frequency selection determines the maximum frequency
on F1 and F2. These outputs are intended to be used to drive
the energy register (electromechanical or other). Since only four
different output frequencies can be selected, the available
F 1–4
V1
V2
V REF
=
=
=
=
1.7 Hz, S0 = S1 = 0
rms of 660 mV peak ac = 0.66/ √ 2 V
rms of 660 mV peak ac = 0.66/ √ 2 V
2.5 V (nominal reference value)
frequency selection has been optimized for a meter constant of
100 imp/kWhr with a maximum current of between 10 A and
120 A. Table V shows the output frequency for several maximum
currents (I MAX ) with a line voltage of 220 V. In all cases, the
Note: If the on-chip reference is used, actual output frequencies
may vary from device to device due to reference tolerance of ± 8%.
meter constant is 100 imp/kWhr.
Table V.
Freq =
5.74 × 0.66 × 0.66 × 1 × 1.7 Hz
2 × 2 × 2 . 5 2
= 0 . 34 Hz
(9)
I MAX
12.5 A
F1 and F2 (Hz)
0.076
As shown in these two example calculations, the maximum
output frequency for ac inputs is always half of that for dc
input signals. Table III shows a complete listing of all maxi-
mum output frequencies.
25 A
40 A
60 A
80 A
120 A
0.153
0.244
0.367
0.489
0.733
Table III.
The F 1–4 frequencies allow complete coverage of this range of
S1
0
0
1
1
S0
0
1
0
1
Max Frequency
for DC Inputs (Hz)
0.68
1.36
2.72
5.44
Max Frequency
for AC Inputs (Hz)
0.34
0.68
1.36
2.72
output frequencies on F1 and F2. When designing an energy
meter, the nominal design voltage on Channel 2 (voltage) should
be set to half scale to allow for calibration of the meter constant.
The current channel should also be no more than half scale when the
meter sees maximum load. This will allow overcurrent signals and
signals with high crest factors to be accommodated. Table VI
shows the output frequency on F1 and F2 when both analog
inputs are half scale. The frequencies listed in Table VI align very
Frequency Output CF
The pulse output CF (calibration frequency) is intended for use
during calibration. The output pulse rate on CF can be up to 128
well with those listed in Table V for maximum load.
Table VI.
times the pulse rate on F1 and F2. The lower the F 1–4 frequency
selected the higher the CF scaling. Table IV shows how the two
frequencies are related depending on the states of the logic inputs
S0, S1, and SCF. Because of its relatively high-pulse rate, the
frequency at this logic output is proportional to the instantaneous
real power. As is the case with F1 and F2, the frequency is derived
from the output of the low-pass filter after multiplication. However,
because the output frequency is high, this real power information
is accumulated over a much shorter time. Hence, less averaging
S1
0
0
1
1
S0
0
1
0
1
F 1–4
1.7
3.4
6.8
13.6
Frequency on F1 and F2 –
CH1 and CH2
Half-Scale AC Inputs
0.085 Hz
0.17 Hz
0.34 Hz
0.68 Hz
is carried out in the digital-to-frequency conversion. With much
less averaging of the real power signal, the CF output is much
more responsive to power fluctuations (see Figure 2).
REV. 0
–15 –
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
EVAL-ADE7752AEBZ
BOARD EVALUATION FOR ADE7752A
EVAL-ADE7753ZEB
BOARD EVALUATION AD7753
EVAL-ADE7754EBZ
BOARD EVALAUTION FOR ADE7754
EVAL-ADE7755ZEB
BOARD EVALUATION FOR AD7755
EVAL-ADE7758ZEB
BOARD EVAL FOR AD7758
EVAL-ADE7759EBZ
BOARD EVALUATION FOR ADE7759
EVAL-ADE7762EBZ
BOARD EVALUATION FOR ADE7762
EVAL-ADE7763ZEB
BOARD EVALUATION FOR ADE7763
相关代理商/技术参数
EVAL-ADE7752AEB
制造商:Analog Devices 功能描述:EVAL BD THREE PHASE ACTIVE ENERGY MET IC - Bulk
EVAL-ADE7752AEBZ
功能描述:BOARD EVALUATION FOR ADE7752A RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081
EVAL-ADE7752EB
制造商:AD 制造商全称:Analog Devices 功能描述:Three Phase Energy Metering IC with Pulse Output
EVAL-ADE7753ZEB
功能描述:BOARD EVALUATION AD7753 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081
EVAL-ADE7754EB
制造商:Analog Devices 功能描述:EVALUATION BOARD FOR POWER METERING, POLYPHASE MULTIFUNCTION ENERGY METERING IC WITH SERIAL PORT 制造商:Analog Devices 功能描述:PWR METERING, POLYPHASE MULTIFUNCTION ENERGY METERING IC W/ - Bulk
EVAL-ADE7754EBZ
功能描述:BOARD EVALAUTION FOR ADE7754 RoHS:是 类别:编程器，开发系统 >> 评估演示板和套件 系列:- 标准包装:1 系列:- 主要目的:电信，线路接口单元（LIU） 嵌入式:- 已用 IC / 零件:IDT82V2081 主要属性:T1/J1/E1 LIU 次要属性:- 已供物品:板，电源，线缆，CD 其它名称:82EBV2081
EVAL-ADE7755EB
制造商:Analog Devices 功能描述:EVAL BOARD ENERGY METERINGW/PULSE OUTPUT - Bulk
EVAL-ADE7755EBZ
制造商:AD 制造商全称:Analog Devices 功能描述:Energy Metering IC with Pulse Output