D U N I W A Y S T O C K R O O M C O R P .
26 of 30
V Application Note
Protective Circuits for Set Point Relays
A. Rated Voltage vs. Current – Resistive Loads
The graph below shows the relationship between the maximum voltage and
current ratings specified for Heavy Duty Type AZ5 relays. These relays are used as
Set Point Relays in the Terranova 9XX 1/8 DIN Vacuum Gauge Control Display
products.
For resistive loads maximum current varies from 2 amps at 30 VDC (60
VAC) downward to 0.4 amps at 150 VDC (300VAC).
B. Protective Circuits for Non-Resistive Loads
For application of the Set Point relays for switching inductive or capacitive
loads, it is advisable to use so-called “snubber” circuits, consisting of
capacitors and resistors across the load. Such a circuit is shown in the
diagram below. This circuit quenches any surges or arcs that might occur
when switching such non-resistive loads.
TELEPHONE: 650-969-8811 TOLL-FREE (U.S. only): 800-446-8811 FAX: 650-965-0764 EMAIL: [email protected]
www.duniway.com
