Reference standards and values

Unless expressly indicated otherwise, the products shown in this catalogue are designed and manufactured according to the requirements of the following European and International Standards:

EN 61810-1 ed. 2, EN 61810-2, EN 61810-7 for electromechanical, elementary relays

EN 50205 for relays with forcibly guided contacts

EN 61812-1 for timers

EN 60669-1 and EN 60669-2-2 for electromechanical step relays

EN 60669-1, EN 60669-2-1 and EN 60669-2-3 for light-dependent relays, electronic step relays, light dimmers, staircase switches and movement detectors. Other important standards, often used as reference for specific applications, are:

EN 60335-1 and EN 60730-1 for domestic appliances

EN 50178 for industrial electronic equipments


According to EN 61810-1, all technical data is specified under standard conditions of 23‹C ambient temperature, 96 kPa pressure, 50% humidity, clean air and 50 Hz frequency. The tolerance for coil resistance, nominal absorption and rated power values is  10%. Unless expressly indicated otherwise, the standard tolerances for mechanical drawings are } 0.1 mm.

Operating & installation conditions

Coil operating range: In general, Finder relays will operate over the full specified temperature range, according to: .

Class 1 . 80% to 110% of nominal coil voltage, or .

Class 2 . 85% to 110% of nominal coil voltage.

Outside the above Classes, coil operation is permitted according to the limits shown in the appropriate  chart. Unless expressly indicated otherwise, all relays are suitable for 100% Duty Cycle (continuous energisation) and all AC coil relays are suitable for 50 and 60 Hz frequency.

Excessive peak voltage limiting: Overvoltage protection (varistor for AC,
diode for DC) is recommended in parallel with the coil for nominal
voltages . 110 V for the relays of 40, 41, 44, 46 series.

Residual current: When AC relay coils are controlled via a proximity switch, or via cables having length > 10 m, the use of a  gresidual current bypass module is recommended, or alternatively, fit a resistor of 62kOhm/1 watt in parallel with the coil.

Ambient temperature: The Ambient temperature as specified in the relevant specification and chart relates to the immediate environment in which the component is situated, as this may be greater than the ambient temperature in which the equipment is located. Refer to page IX for more detail.

Condensation: Environmental conditions causing condensation or ice formation in the relay are not permitted.

Installed orientation: The componentfs specification is unaffected (unless expressly stated otherwise) by its orientation, (provided it is properly retained, eg by a retaining clip in the case of socket mounted relays).

RC contact suppression: If a resistor/capacitor network is placed across a contact to suppress arcing, it should be ensured that when the contact is open, the leakage current through the RC network does not give rise to a residual voltage across the load (typically the coil of another relay or solenoid) any greater than 10% of the loadfs nominal voltage - otherwise, the load may hum or vibrate, and reliability can be affected. Also, the use of an RC network across the contact will destroy the isolation normally afforded by the contact (in the open position).

Guidelines for automatic flow solder processes

In general, an automatic flow solder process consists of the following stages

Relay mounting: Ensure that the relay terminals are straight and enter the PC board perpendicular to the PC board. For each relay, the catalogue illustrates the necessary PC board hole pattern (copper side view). Because of the weight of the relay, a plated through hole printed circuit board is recommended to ensure a secure fixation.

Flux application: This is a particularly delicate process. If the relay is not sealed, flux may penetrate the relay due to capillary forces, changing its performance and functionality. Whether using foam or spray fluxing methods, ensure that flux is applied sparingly and evenly and does not flood through to the component side of the PC board. By following the above precautions, and assuming the use of alcohol or water based fluxes, it is possible to satisfactorily use relays with protection category RT II.

Preheating: Set the preheat time and heat to just achieve the effective evaporation of the flux, taking care not to exceed a component side temperature of 100. Soldering: Set the height of the molten solder wave such that the PC board is not flooded with solder. Ensure the solder temperature and time are kept to 260 (500F) and 3 seconds maximum.

Cleaning: The use of modern gno-cleanh flux avoids the necessity of washing the PC board. In special cases where the PC board must be washed the use of wash-tight relays (option xxx1 - RT III) is strongly recommended. After cleaning it is suggested to break the pin on the relay cover. This is necessary to guarantee the electrical life at maximum load as quoted in the catalogue; otherwise ozone generated inside the relay (dependent on the switching load and frequency) will reduce the electrical life. Even so, avoid washing the relay itself, particularly with aggressive solvents or in washing cycles using low temperature water, as this may cause thermal shock to the PC board components. The user should establish compatibility between his cleaning fluid and the relay plastics. II