Why can I not write setpoints or control dosing from ModbusCloud?

Peraqua has disabled writing to registers on the iQntrol SALT-COMPLETE for safety reasons. The RS485 interface is read-only by design. All setpoint changes must be made directly on the device.

Communication fails even though wiring looks correct. What should I check?

Confirm that the baud rate is set to 57600 on the gateway. This is higher than the typical Modbus default of 9600. Also verify 8 data bits, 1 stop bit, and no parity. A mismatch in any of these settings will prevent communication.

What does the error code register indicate?

The error code register reports faults detected by the iQntrol SALT-COMPLETE, such as probe failures or dosing issues. Refer to the Peraqua device manual for the specific meaning of each error code value.

Do I need a termination resistor on the RS485 bus?

If the gateway is at the end of the RS485 bus or the cable run is long, enable or install a 120 ohm termination resistor at the last device on the bus to ensure reliable communication at 57600 baud.

How it works Pricing

Try the demo Shop

Dutch company. EU-hosted. GDPR-compliant.

Product

Gateway
Shop
Diagnostics
How it works
Pricing
Try the demo

Company

About us
Knowledge Base
Templates
Contact

Legal

Privacy policy
Terms and conditions
Data Processing Agreement
Cookies
Impressum

Free Modbus template: iQntrol salt electrolysis SALT-COMPLETE | ModbusCloud

/// iQntrol salt electrolysis SALT-COMPLETE

Modbus RTU

iQntrol salt electrolysis SALT-COMPLETE

Name: iQntrol salt electrolysis SALT-COMPLETE
Brand: Peraqua
SKU: e4e0fc10-4ef1-4cec-9203-c4e97a792c4f

Peraqua

Monitors pool water chemistry and salt electrolysis parameters via RS485

Overview

Template for the Peraqua iQntrol SALT-COMPLETE salt electrolysis system. Reads pool water chemistry values including pH, ORP, water temperature, and error codes over Modbus RTU (RS485) at 57600 baud. All registers are read-only for safety reasons.

Key readings

pH actual value
pH target value
ORP actual value
ORP target value
Water temperature
Error code

Use cases

Monitor live pH and ORP values on a cloud dashboard to verify water quality without visiting the pool site.
Create an alert when the error code register changes from zero, indicating a fault in the salt electrolysis system.
Track water temperature trends over time to correlate seasonal changes with chemical dosing behavior.
Compare actual pH and ORP readings against their target values to detect probe drift or dosing issues early.
Manage multiple pool installations from a single ModbusCloud account and reduce the frequency of on-site inspections.

Installation

1Connect the RS485 A and B terminals of the ModbusCloud gateway (MCG or MLP series) to the corresponding RS485 terminals on the iQntrol SALT-COMPLETE control unit.
2Configure the serial port on the gateway to 57600 baud, 8 data bits, 1 stop bit, and no parity to match the iQntrol SALT-COMPLETE settings.
3Set the correct Modbus slave address on the gateway to match the address configured on the iQntrol SALT-COMPLETE unit.
4Import the Peraqua iQntrol SALT-COMPLETE template from the ModbusCloud template library into your project.
5Verify that pH, ORP, temperature, and error code values appear correctly on the ModbusCloud dashboard after the first poll cycle.

Things to watch for

Why can I not write setpoints or control dosing from ModbusCloud?: Peraqua has disabled writing to registers on the iQntrol SALT-COMPLETE for safety reasons. The RS485 interface is read-only by design. All setpoint changes must be made directly on the device.
Communication fails even though wiring looks correct. What should I check?: Confirm that the baud rate is set to 57600 on the gateway. This is higher than the typical Modbus default of 9600. Also verify 8 data bits, 1 stop bit, and no parity. A mismatch in any of these settings will prevent communication.
What does the error code register indicate?: The error code register reports faults detected by the iQntrol SALT-COMPLETE, such as probe failures or dosing issues. Refer to the Peraqua device manual for the specific meaning of each error code value.
Do I need a termination resistor on the RS485 bus?: If the gateway is at the end of the RS485 bus or the cable run is long, enable or install a 120 ohm termination resistor at the last device on the bus to ensure reliable communication at 57600 baud.

Working with Modbus in your projects?

ModbusCloud is the hardware-plus-software platform that installers use to monitor, visualise and control Modbus devices from one portal. This template is one of hundreds you can use right away.

See the live demo How it works

More Peraqua templates

iQntrol SALT-MODBUS salt electrolysis | TOUCH EVO PLUS

Peraqua

Modbus RTU

Controls salt electrolysis pool water treatment with real-time pH, ORP, and PPM monitoring.

35 registers44

iQntrol Dosieranlage DOS-COMPLETE Redox-CLF

Peraqua

Modbus RTU

Monitors pool water treatment parameters via RS485 for dosing systems

0 registers36

Ocean Poolpump Inver iQ 300

Peraqua

Modbus RTU

Controls a variable-speed pool pump via Modbus RTU for energy-efficient filtration

23 registers21

iQntrol dosing system DOS-NET

Peraqua

Modbus RTU

Monitors pool water treatment parameters via RS485 interface

0 registers20

iQntrol DOS-MODBUS dosing system

Peraqua

Modbus TCP

Monitors and controls pH/Redox dosing for private pool water disinfection.

43 registers16

More RTU templates

Alnor HRU-P

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTU

Controls Alnor HRU-P heat recovery ventilation units via Modbus RTU.

49 registers7

Alnor HRU

Alnor Systemy Wentylacji Sp. z o. o.

Modbus RTU

Controls and monitors Alnor heat recovery ventilation units via Modbus RTU.

29 registers13

Wattsonic - Schmachtl Sun Energy Box

Wattsonic

Modbus RTU

Monitors Schmachtl Wattsonic hybrid inverter via Modbus RTU

92 registers72

Heidelberg Wallbox Energy Control

AMPERFIED GmbH

Modbus RTU

Controls and monitors Heidelberg Wallbox Energy Control EV charger via Modbus RTU.

22 registers67

connecdoor.controller

connecdoor

Modbus RTU

Controls and monitors smart door access points via RS485

0 registers53

Belimo Air-Water Actuator Modbus RTU

Belimo

Modbus RTU

Controls communicative damper and valve actuators via Modbus RTU.

20 registers46

Specifications

Protocol: Modbus RTU
Brand: Peraqua
Registers: 0
Compatible models: iQntrol SALT-COMPLETE
Last updated: 17 April 2026

Want to professionalise your projects?

EU-hosted

Data in the Netherlands and Germany

Open standard

Based on Modbus RTU/TCP

Free to browse

No account or payment required

European company

Based in the Netherlands