A Timer Relay is a control relay with a time delay function built in. They serve as a combination of an electromechanical output relay and a control circuit, in which contacts can be opened or closed before or after a pre-selected timed interval. Relays can be normally open or normally closed and can be used to delay timed functions from milliseconds to hours or even days.
Timer Relays are triggered/initiated by either:
- Voltage being applied or
- The closing or opening of a trigger signal
How Does a Timer Relay Work?
Timer relays operate by incorporating a time-delay function into a standard relay mechanism. When an electrical signal is applied to the timer relay, it activates an internal timing circuit that controls the relay's contacts.
Depending on the type of timer relay, such as delay on timer or off delay timer, the contacts will either open or close after a predetermined time interval. This delay function allows for precise control in various applications, including automation and process control.
Timer relays are programmable and can be set for specific time intervals, ranging from milliseconds to several hours, and are available in different voltage ratings, such as 12V, 24V, and 240V, to suit different system requirements.
Timer Relay or Electromechanical Relay?
The difference between a timer relay and an electromechanical relay lies in how the output contacts open or close. In a conventional control relay, the contacts open or close immediately when a voltage is applied to or removed from the coil. However, for timer relays, the contacts open or close before or after a specified time period. When choosing the right timer relay, it is important to consider the type of delay required for your application.
What are the Types of Timer Relays?
The most common timing function of Delay Relay are:
- On Delay (Time delay starts on the application of voltage)
- Off Delay (When a voltage is applied the relay is ready to accept a trigger)
- Single Shot (One-shot)
- Interval On (Interval) and Flasher (On First / Off First)
- Repeat Cycle (When a voltage is applied the relay contacts change state and the timer starts)
When designing your application, it is important to understand the difference between the types of the Timer Delay Relays, considering what should initiate the delay and if it should start at the same time as the application, as well as when the voltage is released.
Industrial Applications of Timer Relays
Delay Relays are typically used in industrial applications and OEM equipment play an important role for many industrial processes such as small panel or sub-panels requirements.
Lighting circuits
Timer relays are used in lighting circuits to control the timing of lights turning on and off. For example, a countdown timer relay can be programmed to turn off warehouse lights after a set period, conserving energy and reducing costs when the area is unoccupied. Additionally, an electronic timer relay can be used in outdoor lighting to turn lights on at dusk and off at dawn, ensuring consistent lighting without manual intervention.
Motor start control
In motor start control applications, timer relays ensure a delayed start to prevent sudden inrush currents that can damage motors. For instance, a delay on timer relay is used to sequence the startup of multiple motors in a manufacturing line, reducing the load on the electrical system. A 12v timer relay can be utilised in smaller motor applications, providing precise control in compact setups.
Sensitive equipment
Timer relays protect sensitive equipment by providing delayed activation or deactivation. For example, an off delay timer relay can be used to keep cooling fans running for a set period after equipment is shut down, ensuring adequate cooling and preventing overheating. A timer relay switch can also be employed to gradually power down sensitive laboratory equipment, minimising wear and tear.
Safety control
In safety control systems, timer relays are used to ensure proper timing sequences for safety protocols. For example, a repeat cycle timer can intermittently activate alarms or warning lights in hazardous areas, ensuring continuous safety alerts without manual intervention. An off delay relay can be used to maintain emergency lighting for a set period after a power outage, enhancing workplace safety.
Conveyor belt sequence delay
Timer relays are essential in conveyor belt systems to control the sequence of operations. For example, a programmable timer relay can be set to start and stop different sections of a conveyor belt in a predetermined sequence, ensuring smooth material handling and preventing jams or overloads. A cycle timer relay can also be used to synchronise the operation of multiple conveyor belts, optimising the flow of materials through a production line.
How to Order Timer Relays from RS
RS is a trusted supplier and distributor of timer relays, offering a comprehensive range of high-quality products from leading brands such as RS PRO, ABB, Omron, Schneider Electric. Our extensive selection ensures that you can find the perfect timer relay for your specific application needs.
To place an order, simply browse the RS website and use the filter options to narrow down your choices based on your requirements. You can filter by brand to find products from your preferred manufacturers, or select the appropriate supply voltage, from 12V timer relay to 24V timer relay, 240V timer relay and more.
Filter options also include mounting type, such as DIN rail or panel mount, and timer functions like delay on timer, off delay timer, pulse timer relay, or programmable timer relay. You can also specify the mode of operation, including on-off cycling, delay on break, and repeat cycle functions, to ensure you get the exact functionality you need.
Once you’ve found your desired timer relay, add it to your cart and proceed to checkout. RS ensures a smooth and efficient ordering experience, providing reliable timer relays for all your industrial and commercial applications.
**Delivery Information for Australia **
For efficient delivery of our timer relay and other products across Australia, we recommend placing your orders by 5 pm AEST on weekdays. RS provides next-business-day delivery for products available in our local inventory.
However, please note that deliveries to some remote areas might take longer. To explore our full range of delivery services, which include expedited same-day delivery and options for consolidated shipments, please refer to our delivery information page for detailed guidance