Great Plains NP30A 30-foot Operator Manual User Manual
Page 107
Great Plains Manufacturing, Inc.
Troubleshooting
103
2014-05-20
407-502M
Metering System Troubleshooting
Problem
Cause
Solution
Pressure Spikes
(no alarm)
Plugged knives or tines
Stop application per page 76. Lift applicator and inspect
knives or tines. Clear any plugging per “Clearing Plugged
Knives or Tines” on page 112.
Flow divider
pressure sag
Open delivery line or lines
Stop application per page 76. Lift applicator and inspect
knives or tines for open line plugging. Clear any plugging per
“Clearing Plugged Knives or Tines” on page 112
Temperature Rise
(no alarm)
Plugged refrigerant vapor line Stop application per page 76. Lift applicator and inspect
knives or tines. Clear any plugging per “Clearing Plugged
Knives or Tines” on page 112.
Rate Alarm, Low
System not fully charged
Expect early rate alarms until the cooler is ensuring that all
meter flow is liquid.
One or more manual valves
not fully open
Suspend operations (per page 75). Check all manual valves
from nurse tank withdrawal valve to emergency shut-off
valve.
Solenoid or control valve
malfunction or harness status
Suspend operation (page 75).
Close emergency shut-off valve.
Discharge line from emergency shut-off valve to knives or
tines.
Wait for applicator to be safe to approach.
Check harness connections and fuses.
Use console SELF-TEST mode to command Raven valves
open. Check valve ball indicators at valves.
Field speed too high (higher
than available pressure can
supply NH
3
)
Slow down, or wait for warmer conditions.
Tank pressure low
Ambient or tank temperature may be too low to provide
sufficient delivery pressure. Wait for tank to warm, or wait for
warmer weather.
Rate Alarm, High
Incorrect VALVE CAL for
Control Valve or METER CAL
for flow meter.
Recheck console setup against values provided for
components (page 39).
Control Valve failed, or
harness status
Suspend operation (page 75).
Close emergency shut-off valve.
Discharge line from emergency shut-off valve to knives or
tines.
Wait for applicator to be safe to approach.
Check harness connections and fuses.
Use console SELF-TEST mode to command rate to zero
open. Check valve ball indicators at valves. Command rate
to maximum. Check ball indicator.
Excess NH
3
Remaining
(but no alarms)
Incorrect console setup
Re-check METER CAL and BOOM CAL.
Field size different.
After ruling out metering problems, re-check geography.
Excessive gaps between
fertilizer applicator passes.
Gap between opposing pass end trenches should be one
row space (e.g. 30in)
Flow meter malfunction
Consult dealer.