current meter maintenance hs model osspc1
DESCRIPTION
Current Meter Maintenance HS Model OSSPC1. Hydrological Services Pty Ltd Presented to HiQ Engineering Brunei JULY 2009. Why Is This Important?. Ensures that induced errors in measurement from ‘mechanical’ sources are eliminated Prolongs life of current meter and components. - PowerPoint PPT PresentationTRANSCRIPT
Current Meter Maintenance HS Model OSSPC1
Hydrological Services Pty Ltd
Presented to HiQ EngineeringBrunei
JULY 2009
• Ensures that induced errors in measurement from ‘mechanical’ sources are eliminated
• Prolongs life of current meter and components
Why Is This Important?
Section 1Prior to Gauging
Procedure
Important Points•Dispose of used current meter oil in a thoughtful manner
•Place components on lint free cloth or paper
•Ensure components do not come into contact with dust
•Use ONLY approved HS current meter oil (PYG-17)
Spin Test
• Prior to spin test hold the current meter in the horizontal position, with fan facing directly to your mouth
• Blow air forcefully and allow fan to spin for approx. one minute (to minimise any hydraulic pressure )
DO NOT SPIN BY HAND
Spin Test
• Spin test the meter against time (as per table shown)
• Connect current meter to the counter and test operation
Fan No. Minimum Time (secs)
1 36
3 13
5 11
Fan No. Minimum Time (secs)
1 40
3 15
5 13
Shaft Diameter 4.0mm
Shaft Diameter 2.5mm
Section 2During and After Discharge
Measurements
General Rule
After every discharge measurement, (or one hour of use), the current meter should be disassembled, cleaned, re-filled with oil and reassembled, if continuing a discharge measurement.
Procedure
• Remove fan from meter shaft and dispose of used oil from meter body
• Disassemble meter as shown in Section 1
• Undo the cleaning jar cap and ‘¾ fill’ with white spirit
• Place components on lint free cloth or paper (do not place in contact with dirt particles)
• Place shaft in cleaning jar and agitate in order to flush out used oil
• Fill body of meter with white spirit, place thumb over opening and shake
• Empty and dispose of white spirit from meter body
After Discharge Measurements
• Refill with oil if continuing a gauging
• Blow dry the shaft assembly, fan carrier and fan.
• Assemble ‘dry’ if meter going into storage
After Discharge Measurements
• Spin test the current meter against time as shown in Section 1
• After the spin test is performed connect your current meter to the counter using the lead, to test the lead, reed switch and counter.
Section 3Office Service
When?
• Once per month (if current meter is used regularly (daily?)
•Use same procedure described under Section 2
How?
Section 4Calibration
Calibration•• Re-calibrate the current meter every 300 hours of
use or once a year which ever comes first (see Hydrological Services calibration certificate for
details)
•• To minimise freight costs, send only the body and fans requiring re-calibration
Note: Hydrological Services provides a re-calibration and repair service for all types of current meters.
Section 5Troubleshooting
SYMPTON POSSIBLE CAUSES
ACTION REMARK
Failed spin test Dirty bearings
Faulty bearings
Clean bearings
Replace bearings if problem persists
If fan stops suddenly towards end of spin test, likely cause is dirty bearings
Failed spin test Bent shaft If shaft is bent, return to HS for repair or replace with new shaft
Bent shaft can be observed by looking directly at point of fan during a spin test. If this point is turning ‘off centre’, shaft is bent
Fan out of balance Fan squashed or dropped
Remove the fan, rotate the shaft approx. 50° and re-fit the fan on to the shaft. If problem persists return the fan and body to HS for repair
If fan stops and rotates in opposite direction at end of spin test, this indicates that the fan is out of balance
MECHANICAL PROBLEMS
SYMPTON POSSIBLE CAUSES ACTION
Fault occurs only when meter is immersed in water
Water entering contact plug receptacle and earthing between body and plug
Replace damaged plug (see manual)
Circuit closed in any magnet position, but open with magnet removed
Reed switch failed Replace reed switch assembly
Circuit closed without magnet in position
Reed damaged Replace reed switch assembly
ELECTRICAL PROBLEMS (Closed Circuit Fault)
SYMPTON POSSIBLE CAUSES ACTION
Open circuit between plug and insulated reed contact
Faulty plug contact Clean contact in plug
Re-test
Open circuit between plug and insulated reed contact
Faulty insulated contact assembly
Replace
No closure of reed switch contact when magnet in position
Damaged reed Replace
ELECTRICAL PROBLEMS (Open Circuit Fault)
Questions?