MS Electronics TDS3 - Electrical Requirements; Installation

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Electrical Requirements
Before aempng to install the unit, ensure that the intended load and wiring arrangement comply
with the following requirements. Figure 2 shows a typical wiring example.
• 3-wire (live/neutral + volt-free switch) connecon: The unit requires a permanent live/neutral
connecon, and as such is not suitable for replacing an exisng light switch with no neutral
conductor at the switch locaon. A volt-free relay output is provided, which can be used to
switch a load on the same mains supply (by connecng across from L to LIVE IN, making LIVE
OUT a switched live), or to provide a contact closure to a separate load or control signal. There is
no minimum load requirement.
Also available: TDS2 / TDS2-L (2-wire versions) – Suitable for ‘inline’ connecon with the load to
be switched (no neutral required), such as to replace a standard light switch. A minimum load of
20W (per switch unit) applies; a load capacitor is required for smaller loads.
• Maximum load: The maximum load rang is 16A (4000W), however for high inrush loads (such
as most types of lighng), a lower limit applies: see Technical Specicaon.
Installaon
1. Prepare a single-gang paress or back box as necessary.
2. Rotate the Timeout thumbwheel (referring to the accompanying label) to set the period of me
for which the load should remain switched on aer the buon is touched.
3. Connect the wiring as shown in Figure 2 (or in any suitably appropriate form).
− Supply connecons (L, N): Use appropriate mains cable to power the unit. If the load is also
powered via this wiring, ensure the current rang is adequate. Otherwise (i.e. if the output is
independently powered), low-current cable may be used.
− Load connecons (LIVE IN, LIVE OUT): Use cable rated for the load current and voltage.
− Slave switch connecons (V+, R+, R-) if required: Low-current cable may be used but must
be rated for mains voltages. See Using Mulple Switches for wiring details and slave switch
opons.
4. Fix the unit into posion with the two screws and caps supplied.
Addional Guidelines
• The screw caps may be removed at a later date with the aid of an adhesive puy such as Blu-
Tack.
All electrical installaon and maintenance must be carried out by a competent person. If in doubt,
consult a qualied electrician. Any new wiring must be carried out by qualied personnel in
accordance with the current edion of the IET Wiring Regulaons (BS7671).
Ensure the electrical supply is isolated before making any connecons or adjustments.