What baud rate does the ZTS-3002-TR-THNPKPH-N01 use by default?

4800 bps, 8N1. It is a Modbus-RTU slave; default address 1.

What supply voltage does the ZTS-3002-TR-THNPKPH-N01 need?

DC 4.5–30 V (≤ 0.5 W (24 V DC)).

How do I change the ZTS-3002-TR-THNPKPH-N01 Modbus address?

Write the device-address register with function code 0x06, one device on the bus at a time, then power-cycle. See the Configuration section above.

Is the ZTS-3002-TR-THNPKPH-N01 compatible with the Sankhya platform?

Yes — it is in the Sankhya RS-485 sensor library and the firmware-generation pipeline can produce node firmware for it.

What does the ZTS-3002-TR-THNPKPH-N01 not measure?

The ZTS-3002-TR-THNPKPH-N01 reports moisture, temperature, pH and N-P-K only — it does not report EC, salinity and TDS. On the same RS-485 bus, add EC: ZTS-3000-TR-ECWS-N01; salinity: ZTS-3001-TR-ECTHPH-N01; TDS: ZTS-3001-TR-ECTHPH-N01.

How many Modbus registers does the ZTS-3002-TR-THNPKPH-N01 expose?

This guide documents 8 registers, read with function code 0x03 and written with 0x06 where the register is RW. Documented entries include Soil moisture, Soil temperature, pH, Nitrogen (temporary value), Phosphorus (temporary value) and Potassium (temporary value).

Home / Sensors / ZTS-3002-TR-THNPKPH-N01

ZTS · RS-485 sensor

Zhaotaisheng

ZTS-3002-TR-THNPKPH-N01

Moisture, temp, pH + write-in N-P-K (no live nutrient probe).

✓ Verified for SankhyaMoistureTemperaturepHN-P-KVerification 0.95 · datasheet-confirmed

At a glance

The ZTS-3002-TR-THNPKPH-N01 is a 4-in-1 RS-485 soil probe reporting moisture, temperature, pH and N-P-K over Modbus-RTU on RS-485 at 4800 bps, 8N1, on DC 4.5–30 V. This guide documents 8 registers, default Modbus address 1. It does not report EC, salinity and TDS. For those on the same bus: EC → ZTS-3000-TR-ECWS-N01; salinity → ZTS-3001-TR-ECTHPH-N01. Sankhya firmware profile: ZTS_5in1_noEC.

Quick reference

Bus & electrical specs

Note. ZTS-3002 NPK registers (0x0004–0x0006) are read-WRITE temporaries populated from an external instrument — they are NOT a live soil measurement. Suppress them as agronomic data.

Protocol

Modbus-RTU over RS-485

Default baud

4800 bps

Serial format

8N1

Function codes

0x03, 0x06

Supply voltage

DC 4.5–30 V

Power

≤ 0.5 W (24 V DC)

Default address

Ingress / housing

IP68

Probe / element

Stainless steel

Operating temp.

−40 to +80 °C (probe)

Firmware profile

ZTS_5in1_noEC

Specs sourced from: Official ZTS-3002-TR-N01 datasheet (R224073/R224074).

Modbus-RTU register map

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
0003H	40004	pH	uint16	0.1	pH	RO
0004H	40005	Nitrogen (temporary value)	uint16	1	mg/kg	RW	NOT a live probe reading.
0005H	40006	Phosphorus (temporary value)	uint16	1	mg/kg	RW	NOT a live probe reading.
0006H	40007	Potassium (temporary value)	uint16	1	mg/kg	RW	NOT a live probe reading.
07D0H	42001	Device address	uint16	1	—	RW
07D1H	42002	Baud rate	uint16	1	—	RW	0=2400; 1=4800; 2=9600

Example poll

Worked query

Configuration

Changing address & baud rate

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.

Set the Modbus slave address by writing register 07D0H (PLC 42001) with function code 0x06.
Set the baud rate by writing register 07D1H (PLC 42002). Values: 0=2400, 1=4800, 2=9600.
Power-cycle the probe after a configuration write for the change to take effect.

Field notes

Notes & caveats

Same as ECTHNPKPH variant but without EC register at 0002H. No 0002H register present in this variant.

NPK behaviour. CRITICAL: NPK registers are read/write temporary values — NOT live probe readings.

FAQ

Common questions

What baud rate does the ZTS-3002-TR-THNPKPH-N01 use by default?: 4800 bps, 8N1. It is a Modbus-RTU slave; default address 1.
What supply voltage does the ZTS-3002-TR-THNPKPH-N01 need?: DC 4.5–30 V (≤ 0.5 W (24 V DC)).
How do I change the ZTS-3002-TR-THNPKPH-N01 Modbus address?: Write the device-address register with function code 0x06, one device on the bus at a time, then power-cycle. See the Configuration section above.
Is the ZTS-3002-TR-THNPKPH-N01 compatible with the Sankhya platform?: Yes — it is in the Sankhya RS-485 sensor library and the firmware-generation pipeline can produce node firmware for it.
What does the ZTS-3002-TR-THNPKPH-N01 not measure?: The ZTS-3002-TR-THNPKPH-N01 reports moisture, temperature, pH and N-P-K only — it does not report EC, salinity and TDS. On the same RS-485 bus, add EC: ZTS-3000-TR-ECWS-N01; salinity: ZTS-3001-TR-ECTHPH-N01; TDS: ZTS-3001-TR-ECTHPH-N01.
How many Modbus registers does the ZTS-3002-TR-THNPKPH-N01 expose?: This guide documents 8 registers, read with function code 0x03 and written with 0x06 where the register is RW. Documented entries include Soil moisture, Soil temperature, pH, Nitrogen (temporary value), Phosphorus (temporary value) and Potassium (temporary value).

Alternatives

How this differs from similar models

How the ZTS-3002-TR-THNPKPH-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	Sibling	Moisture, Temperature, EC, pH, N-P-K, Salinity, TDS	4800	Adds EC, salinity and TDS.
ZTS-3001-TR-ECTHPH-N01	Sibling	Moisture, Temperature, EC, pH, Salinity, TDS	4800	Adds EC, salinity and TDS, drops N-P-K.
ZTS-3000-TR-ECWS-N01	Sibling	Moisture, Temperature, EC	4800	Adds EC, drops pH and N-P-K.
ZTS-3000-TR-WS-N01	Sibling	Moisture, Temperature	4800	Drops pH and N-P-K.

Same family

Related ZTS sensors

Run this sensor on a Sankhya node

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.