Title:
FAILURE DETECTION DEVICE FOR USE IN ELECTRODE TYPE WATER-LEVEL GAGE
Document Type and Number:
Japanese Patent JP3678557
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To surely detect a short circuit between electrodes and a failure of a relay, etc., with a simple circuit, by comparing the operation of electrodes immediately above and below the current water level following the water level changes.
SOLUTION: In this device, the water level gage comprises a plurality of electrodes detecting different levels in a water tank, a ground electrode, and electrode relays W1-Wn corresponding to the plurality of respective electrodes. The a-contact of the electrode relay corresponding to the upper electrode and the b-contact of the electrode relay corresponding to the electrode immediately therebelow are connected in series to form series circuits, all of which are connected in parallel, with the operating circuit of alarm equipment A connected in series with the circuits connected in parallel.
Inventors:
Kojiro Kawaguchi
Application Number:
JP27515397A
Publication Date:
August 03, 2005
Filing Date:
September 22, 1997
Export Citation:
Assignee:
Hitachi Kiden Kogyo Co., Ltd.
International Classes:
G01F23/24; G05D9/12; G01F25/00; (IPC1-7): G01F23/24
Domestic Patent References:
| JP3014428U | ||||
| JP1152219U | ||||
| JP8062022A |
Attorney, Agent or Firm:
Osamu Mori
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