Secure Meters CENTAURPLUS C17 Installation Instructions

CentaurPlus C11 & C17 Series 2

Installation Instructions

Horstmann CentaurPlus single channel timeswitches offer up to three

on/off periods a day with a one hour boost and instant advance facility.

Installation and connection should only be carried out by a suitably qualified

person and in accordance with the current edition

of the IEE wiring regulations.

WARNING: Isolate mains supply before commencing installation.

1

Fitting the backplate

Once the backplate has been removed from the packaging please ensure the timeswitch is
re-sealed to prevent damage from dust and debris.

The backplate should be fitted with the wiring terminals located at the top and in a
position that allows a total clearance at last 50mm around the unit.

Direct wall mounting

Offer the backplate to the wall in the position where the timeswitch is to be mounted,
remembering that the backplate fits to the left hand end of the control. Mark the fixing
positions through the slots on the backplate (fixing centres of 60.3mm), drill and plug the
wall, then secure the backplate in position. The slots in the backplate will compensate for
any misalignments of the fixings.

Wiring box mounting

The backplate may be fitted directly onto a single gang steel flush wiring box complying
with BS4662, using two M3.5 screws. CentaurPlus controls are suitable for mounting
on a flat surface only; they must not be positioned on a surface mounted wall box or on
unearthed metal surfaces.

2

Electrical connections

All necessary electrical connections should now be made. Flush wiring can enter from the
rear through the aperture in the backplate. Surface wiring can only enter from beneath the
timeswitch and must be securely clamped. The mains supply terminals are intended to be
connected to the supply by means of fixed wiring. Recommended cable sizes are 1.00 or

2

1.5mm

CentaurPlus timeswitches are double insulated and do not require an earth connection but
an earth connection is provided on the backplate for terminating cable earth connectors.
Earth continuity must be maintained and all bare earth connectors must be sleeved.
Ensure no earth conductors are left protruding outside the central space enclosed by the
backplate.

Internal wiring diagram -
C11 & C17 Series 2

The CentaurPlus has voltage free contacts.
A link L - 2 is required for
mains voltage applications

N L 1 2 3 4

230V 50V COMM OFF ON

New installations

Example circuit diagrams for some typical installations are shown opposite.
These diagrams are schematic and should be used as a guide only.

Please ensure that all installations comply with current IEE regulations.

For reasons of space and clarity not every system has been included and the diagrams
have been simplified - for example some Earth connections have been omitted.

Other control components shown in the diagrams, i.e. Valves, Room Stats etc are general
representations only. However the wiring detail can be applied to the corresponding
models of most manufacturers, for example Honeywell, Danfoss Randall, ACL Drayton etc.

3

Cylinder and Room Thermostat key;

C = Common; CALL = Call for heat or break on rise; SAT = satisfied on rise; N = neutral.

1. Typical combination boiler installation

3. Fully Pumped System with Room Stat and two port spring
return valve (with auxiliary switch) on Heating circuit

2. Typical combination boiler installation with Room Stat

4. Gravity primary with pumped Heating via Room Stat and
Cylinder Stat

Commissioning the timeswitch

Ensure all dust and debris has been cleared away from the work area before removing the
time switch from its packaging.

Rear view of CentaurPlus timeswitch

1 - RATINGS LABEL

1

PULL TO REMOVE

2

3

4

2 - BATTERY

3 - CONNECTOR PINS

4 - PRODUCTION DATE LABEL

+

Battery reserve

The battery must be commissioned prior to fitting the control to the backplate. This is
achieved by the means of a commissioning strip situated in the back of the unit. Pull out
the battery commissioning strip at the back of the timeswitch and re-insert the battery; the
reserve is now activated. When the timeswitch is running the battery reserve clock display
will disappear. This is to prolong the life of the battery.

4

Fitting the timeswitch

If surface wiring has been used, remove the knockout/insert from the
bottom of the timeswitch to accommodate it.

Loosen the two ‘captive’ retaining screws on the bottom of the backplate.
Now fit the timeswitch to the backplate, ensuring the lugs on the
backplate engage with the control.

Swing the bottom of the control into position ensuring that the
connection pins on the back of the unit locate into the terminal
slots in the backplate.

Tighten the two captive retaining screws to fix the unit securely.

Then switch on the mains supply.

End view of CentaurPlus
timeswitch

On completion of the installation please reset the timeswitch - detailed below.

Resetting the timeswitch

On the CentaurPlus press the SET and SELECT buttons together. Then release the
buttons and the timeswitch will return to preset factory settings.
The preset factory settings are illustrated on page 5 or 6 of the USER GUIDE.

SET

SELECT

The unit can now be programmed to suit the user’s requirements.
Please refer to the User Guide provided.

General information

Before handing over the installation to the user, always ensure that the system responds
correctly on all control programmes and that other electrically operated equipment and
controls are correctly adjusted.

Explain how to operate the controls and hand over the users operating instructions to the
user.

5

Specification

CentaurPlus C11 & C17

CONTACT RATING:
3 (1) Amps 230V AC
CONTACT TYPE:
Micro-disconnection
SUPPLY:
230V AC 50Hz only
Pollution Degree 2
CLASS A SOFTWARE:
Type 1 control
OPERATING TEMPERATURE RANGE:
0°C to +40°C
BATTERY LIFE:
10 months continuous operation
(minimum)
CASE MATERIAL:
Thermoplastic, flame retardant
DIMENSIONS:
84mm x 150mm x 29mm

CLOCK:
12 hour AM/PM
Auto BST / GMT changeover
DISPLAY
Back lit liquid crystal
DISPLAYED TIME ADJUSTMENTS:
1 minute steps
SWITCHED TIME ADJUSTMENTS:
10 minute steps
OPERATING PERIODS PER DAY
3 per day
OVERRIDE:
1 hour boost, 1 hour extension to On
period, instant advance
MOUNTING:
Industry standard 6 terminal plug in wall
plate

Horstmann Controls

South Bristol Business Park, Roman Farm Road, Bristol BS4 1UP

E-mail: [e-mail]

Web site: www.horstmann.co.uk

6

Leaflet number P84369 Issue 1