Instruction how to use PZEM_004T_V3 without ESPHome (native Modbus and module Bluetooth TTL):
https://4pda-to.translate.goog/forum/index.php?showtopic=871505&st=33420&_x_tr_sl=ru&_x_tr_tl=en&_x_tr_hl=uk&_x_tr_pto=wapp#entry123597514
Hello, I just got a pzem04t but I feel like the CT cable is very short. If I solder longer wires will it impact in the measurements?
Pretty sure I had to lengthen mine as well. As long as it’s relatively short, you’ll be fine.
Recently, on advise, I received a PZEM004T-V3 and attached it to a Wemos D1 R2 (in ESPhome). Got it working and it gives pretty expected results.
The official documentation, yes I try to read the RTFM, gives the yaml sketch how to give each PZEM a different UART id. The only reason for this can be only when you attach multiple PZEM to one ESP. However the (perfect) yaml sketch and the master/slave UART requirements are a bit missing in this official documentation.
Yes, you can derive this info from the different PZEM topics but it would be nice if best practice is collected in the official documentation. I am too fresh in this topic to update this myself. Anyone?
I notice some people calibrate were other people use the PZEM as-is. Is there still a need for it with V3?
For which case? To connect one or multiple pzem’s to one UART bus? Feel free to change/edit the docs and ad the “perfect” yaml sketch 
No, pzem’s come pre-calibrated and I never noticed people try to calibrate this device 
Any source to this? Tasmota docs even claim that they “can’t” be calibrated - in esphome obviously you could filter the results and use something like calibrate_linear but most likely just make the readings worse with this. 
I wish I could guide other people to the perfect multi PZEM and show them what needs to be done in case single master UART or perhaps the other option of using multi UARTs but that is a bridge too far for me at this point in time. True I can copy and paste but not verify yet if it is all valid,
calibration remark is clear, but even for starters like me a dummy remark could be helpful:
“There is no need to calibrate the PZEM, ESP functions like calibrate_linear will not improve results.”
BTW Did some comparing with an old water cooker and the results were pretty in line. I was able to compare the PZEM (1051w) against Electricity Meter Power consumption phase L2 of DSMR (1049w) yesterday which agrees on this calibration (the cooker itself was 900w but likely the build up whitewash (kalk) residue changed this).
At this point I also not able to improve my github skills and update the documentation because I am on the edge of going on holiday and my girlfriend will drag me from my PC any moment.
Thanks, I did it and it seems working fine.
Another question, if I connect the L and N reversed on the pzem (the 100A version), will it damage it or affect measurements? Or it doesn’t matter?
On the CT? No, it doesn’t matter as it’s AC voltage so it’s ‘going both directions’.
No, I don’t mean the CT. I mean the actual Live and Neutral wires that connect to the pzem. Does it matter or could the be connected indistinctly?
I mean it PROBABLY won’t matter for the same reason, but I would definitely connect it properly. What reason would there be to not do it right?
I see diagrams over internet and the connections of Live and Neutral differ. Here is the one that comes with the manual and here one diagram from tasmota.
I am powering the pzem and esp32 from AC similar to this. So the charger supplies 5V to the esp32, then the esp32 supply 5V to the pzem TTL and at the same time the pzem AC part get its proper power. It might happen that when connecting the plug to the wall, the L and N would be reversed. However, it seems that it doesn’t matter I just tested it and it seems to work just fine.
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Share my working .yaml config 
I have using 6 pzem with esp01s board (VCC <-> 3.3V without any modification on pzem board)
It work normally, but after a few hour, 1 pzem always lost readng data (crc error in logs) another 5 pzem reading fine.
If I remove 1 of pzem cable, another 5 pzem will read data normally.
So I remove 1 pzem out use only 5 pzem and it work fine for month now.
Here is my final version of yaml file that all 5 pzem working fine.
substitutions:
hostname: "esp-pzem"
platform: esp8266
board: esp01_1m
password: "OTA_PASSWD"
ssid: "WIFI_SSID"
psa: "WIFI_PASSWD"
key: "API_KEY"
selfap: "PZEM_SELFAP"
selfpsa: "AP_PASSWD"
esphome:
name: $hostname
platform: $platform
board: $board
logger:
# to disable serial output set baudrate to 0
# baud_rate: 0
api:
encryption:
key: $key
ota:
password: $password
wifi:
ssid: $ssid
password: $psa
ap:
ssid: $selfap
password: $selfpsa
captive_portal:
web_server:
port: 80
#GPIO 2 use for modbus, led can not be use
#status_led:
# pin: 2
time:
- platform: homeassistant
id: esptime
uart:
id: uart_modbus
tx_pin: 0
rx_pin: 2
baud_rate: 9600
data_bits: 8
stop_bits: 1
parity: NONE
modbus:
id: modbus_id
uart_id: uart_modbus
# send_wait_time: 50ms
switch:
- platform: restart
name: "Restart"
text_sensor:
- platform: version
name: version
- platform: wifi_info
ip_address:
name: ip
ssid:
name: ssid
bssid:
name: bssid
sensor:
- platform: wifi_signal
name: "WiFi signal"
update_interval: never
id: wifi_stat
- platform: uptime
name: $hostname Uptime
update_interval: never
id: upt
- platform: pzemac
address: 23 #0x17
update_interval: never
id: pzem1
voltage:
name: "Line Voltage"
id: vol1
frequency:
name: "Line Frequency"
id: freq1
current:
name: "Ch-1 Current"
id: cur1
power:
name: "Ch-1 Power"
id: power1
state_class: measurement
power_factor:
name: "Ch-1 Power Factor"
id: pow_factor1
- platform: total_daily_energy
name: "Ch-1 Total Daily Energy"
id: totaldailyenergy1
unit_of_measurement: kWh
accuracy_decimals: 3
device_class: energy
filters:
- multiply: 0.001
power_id: power1
- platform: pzemac
address: 22 #0x16
update_interval: never
id: pzem2
# voltage:
# name: "Ch-2 Voltage"
# id: vol2
# frequency:
# name: "Ch-2 Frequency"
# id: freq2
current:
name: "Ch-2 Current"
id: cur2
power:
name: "Ch-2 Power"
id: power2
state_class: measurement
power_factor:
name: "Ch-2 Power Factor"
id: pow_factor2
- platform: total_daily_energy
name: "Ch-2 Total Daily Energy"
id: totaldailyenergy2
unit_of_measurement: kWh
accuracy_decimals: 3
device_class: energy
filters:
- multiply: 0.001
power_id: power2
- platform: pzemac
address: 21 #0x15
update_interval: never
id: pzem3
# voltage:
# name: "Ch-3 Voltage"
# id: vol3
# frequency:
# name: "Ch-3 Frequency"
# id: freq3
current:
name: "Ch-3 Current"
id: cur3
power:
name: "Ch-3 Power"
id: power3
state_class: measurement
power_factor:
name: "Ch-3 Power Factor"
id: pow_factor3
- platform: total_daily_energy
name: "Ch-3 Total Daily Energy"
id: totaldailyenergy3
unit_of_measurement: kWh
accuracy_decimals: 3
device_class: energy
filters:
- multiply: 0.001
power_id: power3
- platform: pzemac
address: 20 #0x14
update_interval: never
id: pzem4
# voltage:
# name: "Ch-4 Voltage"
# id: vol4
# frequency:
# name: "Ch-4 Frequency"
# id: freq4
current:
name: "Ch-4 Current"
id: cur4
power:
name: "Ch-4 Power"
id: power4
state_class: measurement
power_factor:
name: "Ch-4 Power Factor"
id: pow_factor4
- platform: total_daily_energy
name: "Ch-4 Total Daily Energy"
id: totaldailyenergy4
unit_of_measurement: kWh
accuracy_decimals: 3
device_class: energy
filters:
- multiply: 0.001
power_id: power4
- platform: pzemac
address: 19 #0x13
update_interval: never
id: pzem5
# voltage:
# name: "Ch-5 Voltage"
# id: vol5
# frequency:
# name: "Ch-5 Frequency"
# id: freq5
current:
name: "Ch-5 Current"
id: cur5
power:
name: "Ch-5 Power"
id: power5
state_class: measurement
power_factor:
name: "Ch-5 Power Factor"
id: pow_factor5
- platform: total_daily_energy
name: "Ch-5 Total Daily Energy"
id: totaldailyenergy5
unit_of_measurement: kWh
accuracy_decimals: 3
device_class: energy
filters:
- multiply: 0.001
power_id: power5
interval:
- interval: 10s
then:
- delay: 150ms
- lambda: "id(pzem1).update();"
- delay: 150ms
- lambda: "id(pzem2).update();"
- delay: 150ms
- lambda: "id(pzem3).update();"
- delay: 150ms
- lambda: "id(pzem4).update();"
- delay: 150ms
- lambda: "id(pzem5).update();"
- delay: 150ms
- lambda: "id(wifi_stat).update();"
- delay: 150ms
- lambda: "id(upt).update();"
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Nice setup, I am interested in the top 2 floors. Did you made them or can you buy them?
what type diodes you have bat45 or same?
I have used bat45
Hi,
I have Wemos D1 mini with PZEM-004T V3 connected as shown in the picture below. The problem I’m struggling with is “Unknown” sensor values.
Code:
esphome:
name: power_consumption
esp8266:
board: d1_mini
# Enable logging
logger:
level: DEBUG
baud_rate: 0
# Enable Home Assistant API
api:
ota:
password: ######
wifi:
ssid: ######
password: ######
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: ######
password: ######
captive_portal:
uart:
rx_pin: GPIO3
tx_pin: GPIO1
baud_rate: 9600
stop_bits: 1
modbus:
sensor:
- platform: pzemac
current:
name: PZEM-004T V3 Current
voltage:
name: PZEM-004T V3 Voltage
energy:
name: PZEM-004T V3 Energy
power:
name: PZEM-004T V3 Power
frequency:
name: PZEM-004T V3 Frequency
power_factor:
name: PZEM-004T V3 Power Factor
update_interval: 30s
I’ve also tried the following:
- Switching to GPIO12/GPIO14 or GPIO4/GPIO5
- Connecting 10k Ohm resistor between 3.3V - TX pin
- Switching RX with TX pin
- Connecting PZEM 5V with WEMOS 3.3V
- Switching CT clamp on hot wire
The sensor was tested in ArduinoIDE giving measurments without any problem, but when connecting to HomeAssistnat I contantly get “unknown” values. I’m only trying to use Wemos with one PZEM so I don’t think I need to address the sensor.
Is level converter necessary to get this think work or there is something wrong with the code?
Any thoughts?
Thanks!
Just asking: Did you test this sensor (PZEM-004T V3) in the Arduino IDE with another device or with the same Wemos D1 mini?
I have a working connection with the combination Wemos D1 R2 / PZEM-004T V3 in ESPhome. In another combination I got a Wemos D1 mini V4 (with USB-C and Ic2 connection, save me to solder ), Both are recognized as:
esp8266:
board: esp01_1m
The other difference with my PZEM-004T V3 / Wemos D1 R2 version is:
# Enable logging
logger:
baud_rate: 0 # Due to TX/RX of Wemos D1 R2
uart:
rx_pin: RX
tx_pin: TX
baud_rate: 9600
Not sure if this will fix your problem. Did not check if you made any typos. Is your log error-less?
I also would recommend to add the web-server:
# include a webserver because it is just very handy during your test phase :D
web_server:
port: 80
include_internal: true
ota: false
local: true
log: false
version: 2
id: webserver
Good luck
good evening, I have a wemos d1 and a PZEM-004T V3 I parameterized it with esphome using vcc of 3.3v, tx, rx, gnd without any other component. the two devices are 2m apart. So far so good until 3 days ago I had to install a further 3 PZEM-004T V3 having modified the 3 addresses set thus 0x02 - 0x03 - 0x04 with the Arduino IDE with esp32. I reconnected everything to the wemos and set everything correctly and it tells me SENSOR UNKNOWN. info this distance is 8 meters without any components.
I have to add something
Ditch the arduino!!! use d1 with tasmota. 50/50 is long cable voltage 3.3V+1k resistor drop to pzem and dont work, or electrical interference on long rx,tx,5v cables.First wrap the rx/tx cable with tin foil,or run pzem with 5v and no 1k resistor
I have all in 3phase rat nest with shotky diodes on d1 rx side, 5v DC for D1 and pzem no 1k resistor and no Pzem adress. Works normal
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Pzem is power hungrey. I have problem with 3.3v and 1k resistor. Works on bench, when in use dont work. seperate 5v line from dc for d1 and pzem
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