Technical data
Enclosure design	Switch cabinet
Output contacts	1 C/O contact
Time function(s)	On-delay
Width	45 mm
Type	AA 7616
Variant
Contact equipping	1 NC contact delayed, 1 NC contact undelayed, 1 NO contact delayed, 1 NO contact undelayed
Nominal voltage	AC 230 V
Time range	0,15 s - 30 h

The Dold time relay AA7616.24AC50/60HZ230V0,15S-30H is a delayed-on time relay of the MINITIMER series, designed for use in industrial control systems and switchgear. It is used for time-delayed activation of devices, for example during motor start-up, to account for the individual starting behaviour of system components. The device operates with a rated voltage of AC 230 V and features a time range from 0.15 seconds to 30 hours, which can be easily and precisely adjusted via stepless rotary switches on the front panel. The housing design is intended for installation in enclosures, with a width of 45 mm.

Applications
This time relay is suitable for applications requiring controlled, time-delayed switching functions. Typical uses include controlling pumps, fans, lighting systems, or other electrical loads where immediate switching is not desired. Its use in industrial environments is supported by its robust mechanical construction and compliance with the standard EN 61812-1, which applies to time relays in industrial electrotechnics.

Functions and Equipment in Detail
The device features a contact configuration with one delayed normally open contact, one instantaneous normally open contact, one delayed normally closed contact, and one instantaneous normally closed contact. This configuration enables parallel control of multiple loads with different delay times. The repeatability is ≤ ± 0.5 %, with a permissible deviation of ≤ ± 1 % in the 3 to 6 second range. This ensures high precision in repeated switching operations. A time progress indicator with a red pointer on the device scale allows visual monitoring of the time progression. Additionally, a switch position indicator is integrated to show the contact status, although this feature is not available in the EH 7616 model series.

Technology Explained Simply
The time relay is based on a purely mechanical time mechanism driven by a synchronous motor. The delay time is adjusted via a stepless rotary switch on the front panel, with six selectable time ranges available. The time function is delayed-on, meaning the contacts only switch after the set time has elapsed. Frequency switching between 50 Hz and 60 Hz is performed on the rear of the device by shifting a latch using a screwdriver.

Compatibility and Accessories
The device is part of the MINITIMER series and can be combined with other models in the series such as EC 7616, EF 7616, and EH 7616, depending on requirements for width and front panel area. The EF 7616 variant, for example, features a front panel with IP 65 protection, making it suitable for applications protected against water jets. The AA 7616 variant is specifically designed for use in enclosures with a width of 45 mm. An optional voltage-loss-safe version is available, which retains the elapsed time in case of power failure.

Mounting and Installation
Mounting is carried out in standard enclosures using screw fastening. The terminals are clearly marked: A1-A2 for control or operating voltage, B1-B2 for control voltage (in versions with B1-B2), and contact terminals 15-16 (delayed normally open), 27-28 (delayed normally closed), 31-32 (instantaneous normally open), and 43-44 (instantaneous normally closed). The delay time is adjusted via the rotary switches on the front panel, with the scale indicating the current setting.

Advantages in Operation
The stepless adjustment of the delay time over a wide range from 0.15 seconds to 30 hours allows flexible adaptation to various applications. The high repeatability ensures reliable and reproducible switching operations. The mechanical construction is low-maintenance and robust, extending the device’s service life. The integrated time progress indicator and switch position indicator facilitate diagnosis and maintenance during operation. Compliance with the standard EN 61812-1 ensures reliability and safety in industrial use.