Kristil Automation Introduction


This is just a general introduction to the Smart House Kristil automation control system.

This is a work in progress. I will add to it as questions are asked or information becomes available.

With that in mind and knowing that there are many home owners and electricians in need of info; if you have information, please let me know so that we can help everyone.

The equipment has changed over the years which means some of this will apply to your installation and some may not. The general concepts should not have varied too much over the years.

To date, this is based on my original design and bits of info picked up along the way.

If you have any comments or questions, Please let me know.

The Equipment

Distribution Panel

The centre of everything. Typically the main power supply and distribution point for the control system. Also where the alarm functions output to sirens, dialler, satellite siren etc.

Power Supply

Generally a 12V nominal supply with battery backup. A UPS may be used to provide backup during mains failure. This has the advantage that the 12V DC supply remains high and steady, not sagging with battery drain. Good for larger installations.

Power and Network Distribution board

This simply supplies fused 12V DC to the network branches. It also connects the network data between the branches.

HUB Boxes

These are spread around the building. They contain the triac/relay modules that handle mains power control. Each Hub Box has a mains circuit feed from the main switch board. The triac/relay modules are connected to their control Switches by point-to-point Cat-5 cables; one cable per switch.

Smart Switch – SS

This is the complicated bit. It is a light switch, the main controller for the area it is in. There can be more than one per area. They are all addressed and connected on the network. The interaction between SSs and programming can be very complex. Don’t swap SSs around unless you know what you are doing and have full programming access.

Each SS on the network has its own address ID.

PIR detector and reed switches are connected to the SS for lighting control and security function. Each SS also has a light sensor and some have a IR remote control receiver.

Simple Switch

A simple control switch of one or three circuits. Drives a triac or relay module. Draws power from the network, but does not communicate on the network. Can have a PIR detector or reed switch connected to provide auto-light function.

Triac Module

This is the dimmer. Typically three dimming circuits. Later modules were longer and included a fourth relay circuit.

Relay Module

A simple output module. Can contain one or more relays. We made one, three and eight channel relay modules.

Wiring Layout

The control network, power and wiring layout can vary. The requirement is to power all components and connect the network between all smart modules.

12V DC nominal power is generally supplied on the network cables, but can be distributed using another larger cable to minimize volt-drop. Volt-drop is bad because it can upset the RS-485 communications.

The power distribution board is supplying 12V DC power to each network branch as well as connecting the network data between all of the branches.

The control network is bi-directional 2-wire RS-485. One pair within the Cat-5 cable carries all data in both directions. One or two pairs within the Cat-5 cable carry 12V power.

The network is “star” connected from the central Distribution HUB, but each leg can have multiple “daisy-chained” smart switches. ie. the Kitchen branch may have 2, 3 or 4 Smart Switches connected along it’s length. Each Smart Switch can be connected to a triac and/or relay module in the kitchen HUB where the power control and dimming is handled. A Smart Switch does not have to connect to a triac/relay module. It could be communicating over the network and controlling lights etc. connected to another Smart Switch.

The cables at the back of the switches are:

  • detectors – network in – network out – triac/relay

Each switch directly connects to one or more triac/relay modules. This is a Cat-5 cable from each switch to the local HUB box.

Typical Problems and Faults

When correctly installed and set up, the system is pretty stable. Problems occur due to incorrect installation, ageing and simple failures.

Incorrect Installation

This is the most difficult to overcome and mostly causes poor communications reliability, which results in randomly unreliable operation. Generally related to network cable runs, power supplies and volt-drop in the power supply between Smart Switches.


This is mostly a power supply problem. As power supplies age, the output becomes less stable and noisy. This makes the system unreliable and very difficult to fault find.

Always check and replace batteries and power supplies first; before tackling other parts of the system.

Simple Failures

Generally, triac module failures. As lamps fail or water gets into outdoor fittings, triac modules fail. This is to be expected. We can repair failed triac modules.