11
Compliance
As soon as scheduling or access permits, but not later than the next 100 Hr inspection
after receipt of required material.
Prior to Modification
Prior to beginning any work, read this entire SOW to ensure a thorough understanding of
the tasks and materials that are required. Any deviation from listed materials is not
authorized unless specifically stated.
Regulatory Authority
An approved Form 337 is attached to this SOW from the FSDO in the jurisdiction where
the prototype SOW installation was completed. As early as possible prior to starting this
SOW, contact your PMI at your area FSDO to determine whether the included 337 will
suffice as approved data for the same installation on your Branch aircraft.
Prerequisite or Concurrent Work
None
Total Estimated Material Cost per Aircraft
$ 500.00
Total Estimated Man-Hours per Aircraft
8 man-hours
SOW Kit
Nomenclature
Part Number
# Required
Low Battery Warning Circuit
AS350-02-24-001
1 ea
Parts Contained in Kit
Nomenclature
Part Number
# Required
Lamp (AMBER)
PC Board
Zenor Diode (6 volt)
Switch (push-to-test)
Wire
AMP Ring Terminal (Red)
In-Line Fuse (EDMO)
Medium Duty Ty-Wraps
Aluminum Sheet Stock
Screw
Washer
Washer (Shimming washer)
Nut
Connector (Plug P1)
Pins (Male)
Connector (Receptacle J1)
Pins (Female)
MS25041-4
TBD
NTE-5070A
MPA-103F
M22759/16-22-9
36152
FHP-1 (1 Amp)
N/A
2024 T3 .032”
AN525-832R12
AN960-8
AN960-8L
MS21044N08
03-06-2042
02-06-2103
03-06-1042
02-06-1103
2
1 ea.
1 ea.
1 ea.
1 ea.
30 Ft.
2 ea.
1 ea.
25 ea.
2”X4”
2 ea.
2 ea.
10 ea.
2 ea.
1 ea.
4 ea.
1 ea.
4 ea.
Special Tools Required
None
References
PC Board Print, RALLC-LoBatt-MES-1 sht. 2 Rev. A
Wiring Diagram, RALLC-LoBatt-MES-1 sht. 1,2,3 Rev. A
DER Form 8110-3 Dated 09/18/02
AC43.13-1B Chapter 11
Accomplishment Instructions
1. Upon receipt of this SOW, load in CARMAC and complete the top portion of form
USCSAVP-110. Send one copy to the PMO to indicate receipt of SOW.
2. Read and understand all notes, cautions and warnings associated with
referenced written procedures and consult MSDS information prior to using any
hazardous chemical required in the accomplishment of this SOW.
3. Remove any attached external power and disconnect the aircraft battery. Tag
aircraft battery and post maintenance area warning placards as necessary.
4. Manufacture an “L” bracket warning light mount from 2024 T3 .032” sheet stock
IAW attached drawing. (DRWG 1)
5. Using the “L” bracket mount as a template locate and drill mounting holes
through instrument panel glare shield for No.8 mounting hardware. (DRWG 2)
6. Mount “L” bracket to underside of glare shield with No.8 screws P/N AN525832R12, washers P/N AN960-8, and nuts P/N MS21044N08. (Photo 1)
Note:
Due to the curvature of the glare shield the “L” bracket should be shimmed
with washers between the bracket and the underside of the glare shield.
Washers will be installed on the inboard mounting screw as necessary to
provide a “Level” appearance.
7. Install lamp assembly, P/N MS25041-4 and switch, P/N MPA-103F in “L” bracket
and secure. (Photo 1)
8. Terminate wires on circuit board assembly, P/N 350-001-01, to connector J1,
P/N 03-06-1042, in accordance with electrical drawing no. RALLC-LoBatt-MES-1
sht. 3 of 3. Use sockets P/N 02-06-1103 for termination.
9. Attach circuit board assembly to underside of avionics shelf behind instrument
panel using No.6 standard hardware. (Photo 2)
10. Route wire no. LoBatt-PWR-22 from switch assembly, installed in step 7, to the
Avionics 28 VDC Buss and terminate wire to fuse assembly F1, P/N-FHP-1.
Ensure adequate length for connection to the Buss in a later step.
11. Route remaining wires from Lamp / Switch Assembly to circuit board assembly
installed in step 9.
12. Terminate wires to connector P1, P/N 03-06-2042, in accordance with electrical
drawing no. RALLC-Lo-Batt-MES-1 sht 3 of 3. Ensure adequate length for
connection to J1 and terminate wires using pin P/N 02-06-2103.
13. Terminate wire no. MES-GND-22 to P1 pin 3 using pin P/N 02-06-2103. Connect
loose end to suitable ground location near circuit board assembly using a red ring
terminal P/N 36512.
14. Route wire no. MES-LP3-22 from lamp assembly to a suitable airframe ground
location. Terminate the loose end with a RED ring terminal P/N 36152.
3
15. Terminate loose end of fuse holder installed in step 10 to the Avionics 28 VDC
Buss using a red ring terminal P/N-36512.
Note
The circuit monitors battery voltage through the “Avionics 28VDC Power
Buss”, any C/B on the buss may be used as a connection point. Ensure that
the connection is made on the “Buss” side of selected C/B.
16. Install locally manufactured placard “Battery Low Voltage” adjacent to the
warning lamp and “Press to Test” adjacent to the Test Switch on the “L” bracket.
17. Route all wiring along with existing aircraft wiring and secure as necessary with
“Ty-Wraps”. Secure in-line fuse holder with “Ty-Wraps” behind instrument panel.
18. Ensure QC inspector final inspection is completed.
19. Release aircraft to designated maintenance personnel for daily and preparation
for flight.
20. Upon completion of this SOW, ensure proper maintenance entries are
documented in aircraft logbook and make appropriate CARMAC entry.
21. Submit completed USCSAVP-110.
4
½”
¼”dia
4”
Note:
1. Material dimensions are not critical
approximations are acceptable.
2. Drill ½” hole for lamp mounting
3. Drill ¼” hole for switch mounting
4. Drill 2ea holes for No.8 mounting
hardware centered with ¾” edge
distance
5. Round edges and paint “Flat-Black”
¾”
90° Bend
½”dia.
¾”
½”
Lamp P/N MS25041-4
2”
Note:
Center and mount lamp bracket between Tq
indicator and T4 indicator while seated in the pilots
seat. The 4” dimension can be adjusted to prevent
visual obstruction of the instruments.
DRWG 1
Glare shield
4”
Instrument
panel
DRWG 2
5
Photo 1
Photo 2
6
7
8
9
10