- Are the heavy-current contacts in the contactors we
have been using single-break or double-break?
- What are some of the advantages of solid-state relays?
(Circle all answers that are correct.)
- a. By looking at the mechanical parts of the relay,
you can tell whether the relay is on or off.
- b. There are no moving parts.
- c. They are resistant to shock and vibration.
- d. They are sealed against dirt and moisture.
- e. The control voltage is isolated from the line
voltage (i.e., there is no electrical connection between the input and
the output).
- Are solid state relays with a power transistor on the
load side used to control DC loads or AC loads?
- Are solid state relays with a triac on the load side
used to control DC loads or AC loads?
- What type of device discussed in Unit 7 is used to
suppress transient voltages? ___________________
- In a solenoid valve, what is the purpose of a shading
coil? ___________________________________
________________________________________________
- Which type of solenoid valve is normally used to
control hydraulic cylinders? Two way or four way.
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