Claims
- 1. A method of controlling a multicircuit control apparatus having a main contact and a plurality of semiconductor switching devices each connected in series with said main contact, said method comprising the steps of:
- an on-operation procedure including a first step of closing said main contact and a subsequent second step of turning at least one of said semiconductor switching devices on; and
- an off-operation procedure including a first step of detecting all of said semiconductor switching devices to be in an off-state and a subsequent second step of opening said main contact.
- 2. A method as in claim 1, wherein:
- said on-operation procedure operates in response to an on-command signal supplied to a control circuit by an input control operation; and
- said off-operation procedure operates in response to a an off-command signal that is for turning, off a final one of said switching devices that is on, said off-command signal being supplied to said control circuit by input control operations.
- 3. A multicircuit control apparatus comprising:
- a main contact which is to be connected to a line from a power source;
- a plurality of semiconductor switching devices, each of which is connected in series with said main contact and is to be connected to a load; and
- a control circuit for discretely controlling said semiconductor switching devices and controlling said main contact only when all of said semiconductor switching devices are in an off-state, said control circuit closing said main contact prior to turning one of said switching devices on when an on-command signal for said one of said switching devices is received, said control circuit opening said main contact only on condition that an off-state of all of said switching devices has first been detected.
- 4. A multicircuit control apparatus comprising:
- a main contact which is to be connected to a line from a power source;
- a plurality of semiconductor switching devices, each of which is connected in series with said main contact and is to be connected to a load; and
- a control circuit for discretely controlling said semiconductor switching devices and controlling said main contact only when all of said semiconductor switching devices are in an off-state, said control circuit closing said main contact prior to turning one of said switching devices on when an on-command signal for said one of said switching devices is supplied by an input control means, said control circuit opening said main contact only on condition that an off-state of all of said switching devices has first been detected.
- 5. The multicircuit control apparatus of claim 2, wherein the control circuit for controlling said main contact and said semiconductor switching devices includes a microcomputer.
- 6. A method as in claim 1, further comprising the steps of a control procedure for turning said semiconductor switching devices on and off with said main contact kept closed.
- 7. A multicircuit control apparatus as in claim 2, wherein the control circuit turns said switching devices on and off in response to respective on-command signals and off-command signals with said main contact kept closed.
- 8. A multicircuit control apparatus as in claim 4, wherein the control circuit turns said switching devices on and off in response to respective on-command signals and off-command signals with said main contact kept closed.
Priority Claims (2)
Number |
Date |
Country |
Kind |
1-244938 |
Sep 1989 |
JPX |
|
1-281264 |
Oct 1989 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 07/585,645, filed Sep. 20, 1990, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2563394 |
Oct 1985 |
FRX |
57-5498 |
Jan 1982 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
585645 |
Sep 1990 |
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