SALUS KL08NSB 24V Wiring Centre

Introduction

The KL08NSB 24V wiring centre is the central component of an Underfloor Heating (UFH) control system. It facilitates easy and rapid connection of thermostats and actuators. The unit features integrated pump and boiler control modules, along with overload protection. The KL08NSB 24V is designed to work with both NC (normally closed) and NO (normally open) type actuators. It supports up to 8 thermostats directly, and with the KL04NSB 24V extension module, it can accommodate an additional 4 thermostats, totaling 12. A 24V/230V transformer is included with the control box set.

Product Compliance

This product adheres to the essential requirements and other relevant provisions of the following EU Directives:

• EMC 2014/30/EU
• Low Voltage Directive LVD 2014/35/EU
• RoHS directive 2011/65/EU

The full text of the EU Declaration of Conformity is available at: www.saluslegal.com.

Safety Information

Use this device in accordance with national and EU regulations. It is intended for indoor use only in dry conditions and must be installed by a qualified person following national and EU regulations. Before setup or installation, ensure the KL08NSB 24V is disconnected from any power source. Incorrect installation may lead to damage. Avoid installing the unit in areas exposed to water or damp conditions.

Technical Information

Wiring Centre Description

The wiring centre features several key components and connection points:

1. Cartridge Fuse 5 x 20 mm 12 A

Note: Replace the fuse only when the wiring centre is disconnected from the 24V~ power supply. The main fuse is located under the housing cover, next to the power supply terminals. It protects the wiring centre and connected devices. Use ceramic tube fast blow 250V ROHS fuses (5x20 mm) with a nominal maximum current of 12.5 A. To replace, remove the fuse holder with a flat screwdriver and pull out the fuse.

Diagram shows a fuse holder labeled '1' with a fuse inside.

2. Power Supply

The wiring centre operates on a 24V AC 50Hz supply. The input is 230V AC, which is converted to 24V AC via the included transformer. Installation should be performed according to applicable regulations.

Diagram shows 230V AC input terminals (L, N) connected to a transformer labeled '230V/24V transformer (in the set)', which outputs to the wiring centre's power terminals (L1, L2).

3. NSB (Night Set Back reduction) Function Terminals & Thermostat Grouping

The NSB function is activated in compatible Salus thermostats (e.g., Expert, HTR series) via an external signal. A 24V NSB signal, typically from an external timer or programmable thermostat connected to the KL08NSB 24V, reduces the setpoint temperature to an eco mode on non-programmable thermostats. All thermostats must be connected using a 4-wire cable (min. 4 x 0.75 mm², max. 4 x 1.5 mm²).

NSB Function Application with Thermostat Grouping:

• OPTION 1: [jumper] present on terminals 1-4 and 5-8. Configuration: One Master thermostat common for thermostats from Group 1 and Group 2 (e.g., HTRP(50) 24V), with other thermostats being non-programmable (e.g., HTR(20) 24V).
• OPTION 2: No jumper. Configuration: Two Master thermostats, one for Group 1 and one for Group 2 (e.g., two HTRP(50) 24V), with other thermostats being non-programmable (e.g., HTR(20) 24V).
• OPTION 3: [jumper] present on terminals 1-4 and 5-8. Configuration: One external clock common for thermostats from Group 1 and Group 2 (e.g., one external clock + daily regulators like HTR(20) 24V).
• OPTION 4: [jumper] present on terminals 1-4 and 5-8. Configuration: Two external clocks, one for Group 1 and one for Group 2 (e.g., two external clocks + non-programmable regulators like HTR(20) 24V).

Diagrams illustrate jumper positions for Options 1-4, showing connections to thermostat groups.

4. NC/NO Jumper (Actuator Type)

This jumper allows selection of the thermoelectric actuator type connected to the wiring centre:

• NC: Actuator normally closed.
• NO: Actuator normally opened.

Note: Jumper position changes require refreshing the memory by pressing the Reset button (short press).

Diagram shows a jumper selector with 'NC' and 'NO' labels.

5. Delay Jumper ⏳

This jumper sets the boiler off delay time. Note: The pump and boiler outputs always start 3 minutes after receiving a heating signal from any connected thermostat. The pump stops 3 minutes after the last heating demand. The heat source (boiler) will turn off after the time set on the Delay jumper.

Note: Jumper position changes require refreshing the memory by pressing the Reset button (short press).

Diagram shows a jumper selector with '0 min' and '15 min' positions.

6. Boiler Control Output ?

This is a volt-free output (COM / NO) that controls the boiler in the heating system. The output closes, turning the boiler on, 3 minutes after receiving a heating signal from any paired thermostat. The output opens, switching the boiler off, when the last thermostat stops sending a heat demand (after the time set on the Delay jumper).

Diagram shows terminals for boiler control (COM/NO) and indicates connection to boiler ON/OFF contacts as per the boiler's manual.

7. Pump Control Output ?

This is a volt-free output (COM / NO) that controls the circulation pump in the heating/cooling system. The output closes (pump starts) 3 minutes after receiving a heating/cooling signal from any paired thermostat. The output opens (pump stops) 3 minutes after the last demand for heat/cool sent by the thermostat.

Diagram shows terminals for pump control (COM/NO) and indicates a maximum load of 3A.

8. Actuators Connection ⚙️

Actuator wires are secured using self-locking connectors in the appropriate zone. Up to 6 actuators, each with a load of up to 2 Watts, can be connected per zone. If more than 6 actuators are needed in a zone, an additional relay is required to relieve the output. Note: 24V AC voltage is present when actuators are live.

Diagram shows terminal blocks numbered 1 through 8 for actuator connections. An example connection for a T30NC 24V actuator is shown, illustrating wire routing.

9. Serial Connector for KL04NSB 24V Extension

This serial connector is used to link the KL08NSB 24V with the KL04NSB 24V extension module, enabling functionality for up to 12 zones.

Diagram shows a serial connector labeled '9' with a connection to a KL04NSB 24V module.

10. Reset Button ?

This button is used to refresh the system data after changing jumper settings (jumper 4 or 5).

Diagram shows a button labeled '10. Reset button'.

11. Thermostats Connection ?️

Various thermostat types can be connected:

• Connecting HTR series thermostats with NSB function (e.g., HTRP24/HTR24): Connects via 230V/24V transformer to terminals L, N, L1, L2. Also includes NSB and SL terminals.
• Connecting RT10 24V thermostat with NSB function: Connects via 230V/24V transformer to terminals L, N, L1, L2. Also includes NSB and SL terminals.
• Connecting ON/OFF battery-powered thermostats (e.g., 091FL, RT310, RT510) with voltage-free COM/NO output contacts: Connects via 230V/24V transformer to terminals L, N, L1, L2.

Note: In NSB, HTR, ERT, BTR product series, the following symbols are used interchangeably: ⬆️ = SL, ⬇️ = NSB.

Multiple diagrams illustrate the wiring for different thermostat types, showing connections to the KL08NSB 24V terminals (L1, L2, SL, NSB, COM, NO) and referencing the 230V/24V transformer.

Installation

Follow these steps for installing the wiring centre:

1. Step 1: Remove the top cover of the wiring centre.
2. Step 2: Unscrew the main housing (refer to picture).
3. Step 3: Mount the back side of the housing to the wall. For DIN rail mounting, open the hooks on the back of the housing.
4. Step 4: Prepare the wires. Remove the appropriate piece of insulation from the wires for the pump/boiler control (min. 2 x 0.75 mm², max. 2 x 1.5 mm²), 24V power supply (min. 2 x 1.0 mm², max. 2 x 1.5 mm²), and thermostat connections (min. 4 x 0.75 mm², max. 4 x 1.5 mm²). The diagrams show specific lengths for stripping insulation (e.g., 12mm, 50mm, 110mm).
5. Step 5: Thread the wires under the mounting belt in the back part of the wiring centre.
6. Step 6: Thread the wires through the slots in the top part of the wiring centre and connect them to the appropriate terminals.
7. Step 7: Adjust the wires and screw the main housing of the wiring centre to the rear housing.
8. Step 8: Connect the thermoelectric actuator wires to their respective terminals.
9. Step 9: Ensure all wires are properly connected. Mount the top cover. Power up the wiring centre; the [red power indicator LED] should illuminate.

The set includes supplementary accessories to support the installation process.

Diagrams illustrate each installation step, showing how to remove covers, mount the unit, prepare and route wires, and connect components.