3PYPA
Table of Contents
Index
Troubleshooting
Great Plains
| 401-647M | 2019-06-11
Table of Contents
Index
91
Seed Pool Recovery
When a meter has been starved of seed, back-flow of air
through the open shutter reduces delivery air flow. This
causes seed delivery to be slow. If you start or resume
planting with an empty seed pool, the delivery flow may
be too low to keep the meter supplied. The steps below
quickly “prime” the meter by rebuilding the seed pool.
Refer to Figure 124 (which depicts a recovery after an
incidence of bridging at air release screen)
1. Close the shutter . This stops the air back-flow.
2. Clear the bridge or blockage that caused the
meter to run empty.
3. With the fan running, listen for seed to fall into the
inlet.
4. Wait for seed fall to taper off and stop.
5. Open the shutter to the operating setting.
6. Start or resume planting.
Magnehelic
a
Gauge Troubleshooting
If the Magnehelic
®
gauge does not read zero with the fan
off, or the reading disagrees with the seed monitor
sensor reading by more than a few tenths of an inch of
water pressure, inspect the gauge, and re-zero as
needed.
Check for chamber and breather line problems before
re-zero. Re-zero cannot accurately compensate for leaks
and blockages.
Re-zero the Magnehelic
®
gauge on level ground with the
fan off, and if possible, under no-wind conditions. Turn
the set screw on the meter face until it reads zero from
the tractor driver’s viewing position.
a. Magnehelic
®
is a registered trademark of Dwyer Instruments, Inc.
Problem
Cause
Solution
Non-zero
with fan off
Zero drift
Re-zero per
instructions below
Gauge
reading
lower than
sensor
Relief port plug
missing/damaged
Replace plug
Breather line blocked
or kinked
Clear breather line
Leak in sensing line
Check line to chamber
Gauge damaged
Check for loose cover,
damaged O-ring
29744
Figure 124
Seed Pool Recovery
29744
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Figure 125
Magnehelic
®
Gauge
29842
Port ID for Troubleshooting:
Over-pressure relief port (with plug in place)
Low-pressure port (breather/atmospheric pressure)
High-pressure port (from manifold chamber)
Alternate high/low ports are plugged.
Winter testing/maintenance advisory:
Gauge readings may be inaccurate or sluggish below 20
F
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