Building on the success of our popular plug-in heavy duty switches, these units provide a hard wired solution to automate high power and inductive loads.
Most timers use a relay, which is a cheap, compact way of controlling resistive loads. Resistive loads do not contain a motor and require a steady amount of current, even on start up e.g. lights.
In contrast, inductive loads contain a motor or coil e.g. power tools, pumps and refrigerators. When an inductive load is first powered up, it draws a much larger start up current, typically 2.5-3 times its normal operating current. For example a 500w drill may briefly draw 1250-1500w when it starts up. The main issue is actually caused when the relay contacts open to turn the tool off. The stored inductive energy in the motor coil is discharged, resulting in a damaging arc across the terminals, which can eventually cause the relay to fail.
To overcome this issue, instead of using the relay within the timer unit to switch the load directly, our units connect the timer to a high quality contactor, which then switches the load.
Contactors work using the same principle as a relay, but they are much larger and far better suited to switching higher current inductive loads. The picture below shows the sheer size difference between a typical contactor (left) and relay (right); when it comes to switching inductive loads, contact size really does make a difference.
Contactor rating:
| Unit | Resistive | Inductive |
| 230v 32A | 40A (AC-7a) | 15A (AC-7b) |
| 415v 32A | 63A (AC-7a) | 20A (AC-7b) |
A Wi-Fi unit is also available as an alternative, to provide remote programming and switching.
Timer Specification:
- Digital programmable time switch.
- Up to 16 on/off periods can be set for each day, minimum 1 min apart.
- Manual over-ride to select permanently on or off.
- Easy to program using clearly marked buttons.
- Battery back-up to retain settings when power is disconnected (continual power provided for up to 3 years).
- Please note that the timer will not work if the appliance connected to it has a DoL motor starter or no-volt release switch (NVR). These commonly both have a start and stop switch.
Enclosure Specification:
- Manufactured from steel, with a steel top hinged lid.
- IP4X rated (protected from physical objects larger than 1mm, with no water ingress rating) for use indoors.
- Light grey finish.
- Complete with earth bar.
- 230v unit dimensions H180xW67xD85mm. 1x 20mm cable knock out at the top, 1x 25mm at the base.
- 415v unit dimensions H238xW125xD102mm. 2x 25mm cable knock out at the top and base.