Technical data
Enclosure design	Front panel mounting
Output contacts	1 C/O contact
Time function(s)	Off-delay, with control signal
Width	48 mm
Type	EC 7666
Variant
Contact equipping	1 NC contact delayed, 1 NO contact delayed
Nominal voltage	AC 230 V
Time range	0,2 s - 60 h

The Dold time relay EC7666.21AC50/60HZ230V0,2S-60H is a delayed-release industrial time relay for front panel mounting, used to control devices and systems with a predefined de-energizing delay. It is suitable for applications such as accounting for the coast-down behavior of motors or other system components that continue to run or decay after the control signal is switched off. The device features a purely mechanical timing mechanism, which can be easily and precisely adjusted via stepless rotary switches on the front. The timing function complies with EN 61812-1 and is designed for use in industrial control systems.

Applications
This time relay is suitable for applications in industrial automation, machine and plant control, as well as building automation. It is used wherever delayed de-energization of switching operations is required, for example with pumps, fans, heaters, or for switching off auxiliary units after the main motor. The zero-voltage safety ensures that the device immediately returns to its default position in case of power failure, which is important for safety in control systems.

Functions and Features in Detail
The device has a contact configuration with one delayed opener and one delayed closer, equivalent to a changeover contact. The delay time can be adjusted steplessly in the range from 0.2 seconds to 60 hours. Adjustment is performed via an indicator pointer on an absolute scale on the front. Repeatability is ≤ ± 0.5 % of the scale end value, with a tolerance of ≤ ± 1 % allowed in the 3 and 6 second ranges. A timing indicator displays the progress of the set delay time. The switching position indicator enables visual monitoring of the contact position, although this feature is not available in the EH 7666 variant.

Technology Explained Simply
The timing mechanism is based on a purely mechanical principle that does not require electronic components. The delay is generated by a mechanical timing mechanism, which is adjusted via a rotary switch. Contacts switch only after the set time has elapsed, with the opener delaying opening and the closer delaying closing. The response time of the contacts is less than 35 ms, and the release time is less than 60 ms. The thermal current rating is 4 A, and the switching capacity is 3 A / AC 230 V according to AC 15 (IEC/EN 60947-5-1). The electrical life is at least 100,000 switching operations at 3 A and AC 230 V, and at least 500,000 switching operations at 1 A. The mechanical life exceeds 30 million switching operations or 15,000 operating hours.

Compatibility and Accessories
The time relay is designed for a nominal voltage of AC 230 V and can be operated within a voltage range of 0.8 to 1.1 times the nominal voltage. The nominal frequency is 50/60 Hz, with a permissible frequency deviation of ±5 % around the nominal frequency. The input power is 7 VA. The rated operating voltage of the contacts is AC 250 V. The maximum fuse rating is 10 A gG / gL. The device is designed for front panel mounting and has a width of 48 mm and a front surface of 48 x 72 mm. It is operated via a control signal supplied through connection terminals A1/A2.

Mounting and Installation
The device is installed in a front panel with a minimum depth of 40 mm. Mounting is done by screwing to the panel. The delay time is adjusted via the rotary switch on the front. The time ranges are switchable and can be selected according to application. The switching position indicator allows checking of the contact position during operation.

Operational Advantages
The wide adjustment range from 0.2 seconds to 60 hours enables flexible adaptation to various applications. The simple adjustment via the stepless rotary switch and the clear display of the timing indicator and switching position indicator facilitate commissioning and maintenance. The zero-voltage safety ensures safe de-energization in case of power failure. The high mechanical and electrical life ensures reliable long-term use in industrial environments. The use of AgNi contacts with a gold plating of 0.2 μm ensures high switching quality and corrosion resistance.