Panasonic ASCT1F46E manual Short current, Arcing, Load

4. Load,	23. Connection
electrical	of load
life

5

Connect the load to one side of the power supply as shown in Fig. (a). Connect the contacts to the other side. This prevents high voltages from developing between contacts. If contacts are connected to both side of the power supply as shown in Fig. (b), there is a risk of shorting of the power supply when relatively close contacts short.

Fig. (a) Good example(b) Bad example

Regarding the following circuit constructions with 2-coil relays (twin relays) or single-pole relays, an arc between contacts may be generated when breaking of load current depending on the type of load current, voltage, and load. Please note that or contact us.

＜2 coil relay (twin relay) or two of single-pole relays＞

	+		+	Short current
Ａ		B		Arcing
			B side OFF
	Load		Load

＜Single-pole relay＞

++

	24. Short
	between
	interelectrodes
5. Coil	1. Hot start
impressed	voltage
voltage

2. Ambient temperature characteristic

3. Applied voltage

Load OFF Load Arcing

When using of multipole relays such as 2-coil relays (twin relays), verify insulation and breakdown voltage between contacts in each pole in order to avoid an accident caused by short.

After continuous applying of current to coil and contacts, if the current is turned OFF then immediately turned ON again, coil resistance and the pick-up voltage will increase due to the temperature rise in the coil.

Temperature rise value of coil is greatly affected by circuit board, connected harness, connected connector, heat dissipation of system/modules, and heat source around relay. Please verify whether it is operating properly or inoperative under actual vehicle and actual use conditions.

Coil resistance and the pick-up voltage will increase when the relay is used in a higher temperature atmosphere. The resistance/temperature coefficient of copper wire is about 0.4% for 1°C, and the coil resistance increases with this ratio. On the other hand, coil resistance and the drop-out voltage will decrease at lower temperature. Coil resistance change decreases with the same ratio at higher temperature, about 0.4% for 1°C.

Therefore, please confirm the relay operation in every operating temperature range, with attention to such temperature characteristic.

The ambient usage temperature should be set as around the relay inside the box because a heat generated by a relay itself or other instruments causes increase of temperature inside the box.

Note that a coil impression with a voltage greater than or equal to the maximum continuous impressed voltage may cause temperature rise which could cause coil burning or layer short. Furthermore, do not exceed the usable ambient temperature range listed in the catalog. Please contact us regarding PWM control.