240D25-17 Datasheet, PDF (11/12 Pages) List of Unclassifed Manufacturers – SOLID-STATE RELAYS

DATA SHEET
Form 859-990514
Applications
Tips (Continued)
SOLID-STATE RELAYS
page 11/12
Solid-State Relays In Series
In applications requiring greater current rating at higher voltage,
two Opto 22 SSRs may be operated in series for double the
voltage rating. The built-in snubber in each SSR assures proper
voltage sharing of the two SSRs in series. In the diagram below,
two 240-volt, 45-amp SSRs are connected in series for operation
on a 480-volt line. The control is shown with a parallel hook-up
but it should be noted that a serial connection can also be
implemented.
Lamp Loads
Since all Opto 22 SSRs are zero voltage switching, they
are ideal for driving incandescent lamps because the
initial inrush current into a cold filament is reduced.
The life of the lamp is increased when switched by a
zero voltage turn on SSR. The following table is a guide
to selecting an Opto 22 SSR for switching a given
incandescent lamp.
120 Volt Lamps
SSR CURRENT RATING LAMP RATING
2-Amp
100 Watt
4-Amp
400 Watt
10-Amp
1 Kilowatt
25-Amp
2 Kilowatt
45-Amp
3 Kilowatt
240 Volt Rating
SSR CURRENT RATING LAMP RATING
2-Amp
200 Watt
4-Amp
800 Watt
10-Amp
2 Kilowatt
25-Amp
4 Kilowatt
45-Amp
6 Kilowatt
Heater Loads
Care should be taken in selecting a SSR for driving a heater load if
the load is cycled on and off in a continuous manner as might occur in
a temperature control application. Constant cycling can cause thermal
fatigue in the thyristor chip at the point where the chip bonds to the
lead frame. Opto 22 employs a thick copper lead frame for mounting
the SCR chips in the power series SSRs to eliminate thermal fatigue
failures. In addition, Opto 22 recommends operating any SSR at 75%
rated current for cycling heater loads to ensure complete reliability.
The following table is a guide to selecting the proper SSR for a given
heater load.
Nominal SSR
Current Rating
2-Amp
4-Amp
10-Amp
25-Amp
45-Amp
10 480V
10 480V
Maximum
Recommended
Heater Current
1½-Amp
2½-Amp
7½-Amp
18-Amp
35-Amp
8-Amp
8-Amp
Opto 22 • 43044 Business Park Drive • Temecula, CA 92590 • Phone: [phone] • (800)321-OPTO • Fax: [phone] • Internet: www.opto22.com
Inside Sales: (800)452-OPTO • Product Support: (800)TEK-OPTO • [phone] • Fax: [phone] • E-mail: [e-mail] • FaxBack: (800)474-OPTO