Home / Sensors / SN-3002-TR-ECTHNPKPH-N01
SN · RS-485 sensor
Puruisenshe (普锐森社)
7-register probe with write-in N-P-K (ZTS-3002-class behaviour).
The SN-3002-TR-ECTHNPKPH-N01 is a 7-in-1 RS-485 soil probe reporting moisture, temperature, EC, pH, N-P-K, salinity and TDS over Modbus-RTU on RS-485 at 4800 bps, 8N1, on DC 4.5–30 V. This guide documents 27 registers, default Modbus address 1. It is register-compatible with the ZTS-3001-TR-ECTHNPKPH-N01, which the same firmware profile reads unchanged. Sankhya firmware profile: ZTS_7in1.
Sankhya Farms has a profile for the SN-3002-TR-ECTHNPKPH-N01 register family and can place its reported moisture, temperature, EC, pH, nutrient, salinity and TDS fields in the free cloud dashboard. The wide register map is useful because one RS-485 address can supply a compact monitoring record, but this model carries a lower verification score than the fully confirmed ZTS-3001 map. N-P-K behaviour should be checked against the exact manual and a known sample before those fields are treated as live agronomic measurements.
For moisture, temperature, EC and pH observation, the same dashboard can serve an orchard, greenhouse, container trial, home garden or media-grown crop. It can also act as a logging surface during bench testing: power the sensor, inspect each returned word, and compare the decoded value with a reference instrument. This is often more useful than a one-off serial-terminal printout because changes and intermittent faults remain visible. For hydroponic reservoirs or water treatment, choose liquid-rated probes even when the desired pH or EC parameter has the same name.
The primary family begins at 0000H: moisture, signed temperature, EC and pH occupy the first four defined addresses; N, P and K are listed at 0004H–0006H; salinity and TDS are 0007H and 0008H. The remaining documented words include conversion, calibration and configuration values and should not be displayed as live measurements. Sankhya maps by address and meaning, not by simply charting every returned integer.
Specs sourced from: Official SN-3001-TR-*-N01 datasheet (R224096); ZTS-compatible register layout.
Function codes 0x03, 0x06 at 4800 bps, 8N1. Data registers are read with 0x03; configuration registers are written with 0x06. PLC column shows the 4xxxx Modbus holding-register convention.
| Register | PLC | Parameter | Type | Scale | Unit | R/W | Notes |
|---|---|---|---|---|---|---|---|
| 0000H | 40001 | Soil moisture | uint16 | 0.1 | % | RO | |
| 0001H | 40002 | Soil temperature | int16 | 0.1 | °C | RO | Negative values in two's complement. |
| 0002H | 40003 | Electrical conductivity | uint16 | 1 | uS/cm | RO | |
| 0003H | 40004 | pH | uint16 | 0.1 | pH | RO | |
| 0004H | 40005 | Nitrogen (actual value) | uint16 | 1 | mg/kg | RO | LIVE probe reading per ZTS-3001 official PDF. Range 1-1999 mg/kg. Accuracy ±2%FS. Different from ZTS-3002 where this is a writable temporary value. |
| 0005H | 40006 | Phosphorus (actual value) | uint16 | 1 | mg/kg | RO | LIVE probe reading per ZTS-3001 official PDF. Different from ZTS-3002. |
| 0006H | 40007 | Potassium (actual value) | uint16 | 1 | mg/kg | RO | LIVE probe reading per ZTS-3001 official PDF. Different from ZTS-3002. |
| 0007H | 40008 | Salinity | uint16 | 1 | mg/L | RO | Reference value only. |
| 0008H | 40009 | TDS | uint16 | 1 | mg/L | RO | Reference value only. |
| 0022H | 40035 | Conductivity temperature coefficient | uint16 | 0.1 | % | RW | 0-100 corresponds to 0.0%-10.0%. Default 0. |
| 0023H | 40036 | Salinity conversion coefficient | uint16 | 0.01 | — | RW | Default 55 (0.55). |
| 0024H | 40037 | TDS conversion coefficient | uint16 | 0.01 | — | RW | Default 50 (0.50). |
| 0050H | 40081 | Temperature calibration value | int16 | 0.1 | °C | RW | |
| 0051H | 40082 | Moisture calibration value | int16 | 0.1 | % | RW | |
| 0052H | 40083 | Conductivity calibration value | int16 | 1 | uS/cm | RW | |
| 0053H | 40084 | pH calibration value | int16 | 0.1 | pH | RW | |
| 04E8H | 41001 | Nitrogen coefficient high word | uint16 | — | — | RW | IEEE 754 float high 16 bits. |
| 04E9H | 41002 | Nitrogen coefficient low word | uint16 | — | — | RW | IEEE 754 float low 16 bits. |
| 04EAH | 41003 | Nitrogen deviation | int16 | 1 | — | RW | |
| 04F2H | 41011 | Phosphorus coefficient high word | uint16 | — | — | RW | IEEE 754 float high 16 bits. |
| 04F3H | 41012 | Phosphorus coefficient low word | uint16 | — | — | RW | IEEE 754 float low 16 bits. |
| 04F4H | 41013 | Phosphorus deviation | int16 | 1 | — | RW | |
| 04FCH | 41021 | Potassium coefficient high word | uint16 | — | — | RW | IEEE 754 float high 16 bits. |
| 04FDH | 41022 | Potassium coefficient low word | uint16 | — | — | RW | IEEE 754 float low 16 bits. |
| 04FEH | 41023 | Potassium deviation | int16 | 1 | — | RW | |
| 07D0H | 42001 | Device address | uint16 | 1 | — | RW | Range 1-254. Factory default 1. |
| 07D1H | 42002 | Baud rate | uint16 | 1 | — | RW | Factory default 1 (4800 bps). 0=2400; 1=4800; 2=9600 |
This probe is configured over the same RS-485 bus using Modbus write commands (function code 0x06). Configure one device at a time on the bus.
SN-3002 is the 7-parameter variant of SN-3001. Given SN-3001 is confirmed identical to ZTS family, SN-3002 almost certainly maps to ZTS_7in1 profile. Verify NPK caveat applies.
How the SN-3002-TR-ECTHNPKPH-N01 compares with the other RS-485 models in the Sankhya library. "Drop-in" means the same parameter set and the same register map, read by the same firmware profile.
| Model | Relationship | Measures | Baud | Difference |
|---|---|---|---|---|
| ZTS-3001-TR-ECTHNPKPH-N01 | Drop-in | Moisture, Temperature, EC, pH, N-P-K, Salinity, TDS | 4800 | Same parameter set and register map. Differs in supply range (DC 5–30 V). |
| SN-3001-TR-ECTHPH-N01 | Sibling | Moisture, Temperature, EC, pH, Salinity, TDS | 4800 | Drops N-P-K. |
Every sensor on this page is in our RS-485 library. Pick your model, and the firmware-generation pipeline builds the Modbus (or ASCII) polling code for an ESP32-S3 node — no hand-coding the register math.
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