Efficiency: 0.8 for a motor < 5kW
Efficiency: 0.9 for a motor > 5kW
Power factor: 0.8 for a motor < 5kW
Power factor: 0.9 for a motor > 5kW
V3 = 1.732
Nominal current absorbed by the motor:
I = 1500/ = 26.7A
(400 x 1.732 x 0.9 x 0.9)
The relay’s current rating must be 4 x I of the motor in order to withstand starting currents:
>>> 106.8A >>> a 125A relay must be used.
With their semiconductors and a technology-based design, SSRs are more reliable, have a longer service life and less electromagnetic interference (EMI) than EMRs. They also have faster response times and are vibration and shock resistant, when compared to the EMR equivalent. This is because SSRs have no mechanical contacts to wear out or an arc, which is the primary cause for EMR failure.
A curve without a heatsink is associated with SO/SC or SG types of solid state relays.
When installed on the back plate of a cabinet, it is essential that the relay/plate contact is correct.
A 150 mm x 150 mm x 3 mm aluminium back plate corresponds to approximately 4°/W.
A 300 mm x 300 mm x 3 mm aluminium back plate corresponds to approximately 2°/W.
In any case, we recommend testing and measuring the heat dissipation.
A steel plate has greater thermal resistance.
The relay will only turn on when the mains (output) voltage is near zero.
When the control voltage is on, the relay will switch on simultaneously, irrespective of the mains voltage value.
Zero cross relays are used with resistive loads while random turn on relays are used with inductive loads (motors, transformers, coils, etc.).
Relay leakage current is too high in relation to the load holding current.
This mainly happens with zero cross SSRs with DC control: the input signal is rectified but not filtered; at zero cross, the input signal is too low to make a valid control signal.
Solution: install a capacitor across the input.
Check whether there is a connection between terminals 5 & 6
This is not possible because of the existing technology being used. In fact, current will always flow through one SSR only.
This is possible, but it must comply with the following conditions:
2 or 3 single-phase relays can be used. Our 75, 95, and 125A SGTs/SVTs are used for loads with non-permanent peak currents (in lamps, motors, etc.), or to provide better protection.
Altitude has an impact on insulation and heat dissipation, both decrease as altitude increases.
Heat dissipation is also less, so it might be necessary to increase the size of the cooling element (heatsink) used with the SSR. Tests must be carried out using a nominal current, in an ambient temperature with a T°C measurement on the heatsink near the relay The temperature should not exceed 100°C.