What Is a Twin Timer?
A twin timer is a type of timer relay function that allows the ON time and OFF time to be set separately.
Flicker operation can be set for timer relays. Flicker operation is an operation in which the ON time and OFF time continue to repeat alternately when a voltage or start signal is applied to the relay.
In a normal flicker operation, only one ON time and one OFF time can be set in common. However, in a timer relay with twin timer function, each of these can be set individually.
Uses of Twin Timers
Twin timers are used in electronic devices and machinery that require separate ON and OFF time settings. Typical examples are lamps and signal towers. Twin timers are also used in other machines that need to be run and stopped at regular intervals.
For example, a twin timer can be used to turn a lamp on for 5 seconds and then off for 3 seconds, or to rotate a gear for 3 seconds and then stop for 5 seconds, or when a device needs to be turned on and off separately.
Principle of Twin Timers
A timer relay consists of four parts: an input part, a timekeeping part, a power supply part, and an output part. The input section receives signals from the device and passes them to the timekeeping section. The timekeeping section measures time and passes the signal to the output section after a set time has elapsed.
The output section then outputs the signal to various devices. The power supply section supplies voltage to the timer relay. When the power supply part of the timer relay is turned on, or when the signal for start is sent to the input part while the power supply voltage is applied, the timer relay starts operating.
Types of Twin Timers
In addition to flicker operation, timer relays have other modes of operation such as on-delay operation, off-delay operation, and interval operation. The twin timer is one of these timer relays that performs flicker operation.
When the timer relay is set to off-start, it repeats the off/on/off sequence, and for on-start, it repeats the on/off/on sequence in reverse. With the twin timer, the on-time and off-time can be set alternately, and this allows the timekeeping unit to either send a signal to the output section or stop the signal.
Other Information on Twin Timers
Types of Twin Timers in Digital Timers
A digital timer is a timer that can be switched on and off after a pre-set numerical period of time has elapsed. The following four types of twin timers in digital timers are available:
They are classified according to whether or not they have a power reset operation and a power holding operation for flicker off start and flicker on start, respectively.
1. Toff Mode
This mode starts timing at the rising edge of the signal input while power is being applied and repeats OFF and ON. A reset occurs when the power supply is turned OFF, and can also be reset by inputting a reset signal other than the power supply or by using the reset key on the main unit.
2. Ton Mode
This mode also starts timing at the rising edge of the signal input, repeating ON and OFF as in the toff mode described above, but differs in that it always starts from ON.
Like toff mode, this mode is reset when the power is turned off.
3. Toff-1 Mode
Like toff mode, this mode starts timing at the rising edge of the signal input while power is being applied, and repeats OFF and ON.
It differs from toff mode in that it retains the previous time even when the power is turned off. After power is applied again, timekeeping starts from the beginning when the signal input turns ON. Reset can be done by inputting a reset signal or by pressing the reset key.
4. Ton-1 Mode
In the toff-1 mode, the timekeeping starts from ON after the rising edge of the signal input and repeats ON and OFF.