Page 66 - IDEC relay catalogue

RSS Series Relays & Sockets

Technical Notes

Switches & Pilot Lights Do not install SSRs near sources of excessive heat. Make sure applications are dry and well ventilated.
Environment

If SSRs must be installed in an environment subject to high temperatures or poor ventilation, or if SSRs are mounted collectively, reduce the load current so that it
does not approach the ambient temperature-load current recommendation. (See the Temperature Derating Curves on the following page.)
When SSRs are used with inductive loads, suppress the inrush current to half of the peak surge current.

Heat Sinks
Heat sinks are recommended for all solid state relays depending on ambient temperature and mounting position. The recommended heat sink dimensions and mate-
rial are shown in the table:
Display Lights Output Rating 12” x 12” x 1/8” Aluminum (black anodized)
Dimensions
Material
10A
25A
15” x 15” x 1/8” (AC/AC)
25A 12” x 12” x 1/8” (DC/AC) Aluminum (black anodized)
Aluminum (black anodized)
50A 15” x 15” x 1/8” Aluminum (black anodized)
75A 17” x 17” x 1/8” Aluminum (black anodized)
90A 17” x 17” x 1/8” Aluminum (black anodized)
Relays & Sockets Using a thermal compound between the base of the SSR and the heat sink for heat dissipation is recommended.

Wiring
Locate SSRs as far from motor leads as possible to prevent malfunction from induced current.
Use shielded wires for input leads when they are exposed to a source of induced current.

Mounting
Provide suffi cient ventilation.

Timers Use #6 – 32 screws, fl at washers, and lock washers to secure mounting on heat sinks.
Vertical mounting is recommended to allow air to fl ow unimpeded. Horizontal or inverted mounting is possible, but the SSR must be derated according to the derating
curves on the following page.

Additional Information
Do not exceed the load voltage and current specifi cations.
A small-capacity load may not turn off due to the leakage current present after the SSR has turned off. If this is the case, use a resistor in parallel with the load to
Terminal Blocks shunt the leakage current.

Observe the polarity of input terminals. Failure to do so may cause damage to the SSR.
When the SSR output is subjected to a higher than rated voltage, a varistor or other element should be connected to the output terminals to absorb the over-voltage.

When the input signal contains a ripple voltage, the lowest ripple amplitude should exceed the minimum pick-up voltage of 4V.

Over 4V Lowest Voltage
Circuit Breakers 0V

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