U.S. Department 

of Transportation 

Federal Aviation 

Administration

Advisory 

Circular 

Subject: SPECIFICATIONS FOR AIRPORT 

LIGHTING CIRCUIT SELECTOR SWITCH

Date: September 14, 2006

Initiated by: AAS-100 

AC No: 150/5345-5B 

Change:

1. PURPOSE. This advisory circular (AC) contains a specification for a circuit selector 

switch for use in airport lighting circuits. 

2. EFFECTIVE DATE. Effective 6 months after the issue date of this advisory 

circular, only that equipment qualified in accordance with the specifications contained in 

this AC will be listed in AC 150/5345-53, Airport Lighting Equipment Certification 

Program, current edition. 

3. CANCELLATIONS. This AC cancels AC 150/5345-5A, Specification for L-847 

Circuit Selector Switch, 5,000 Volt 20 Ampere, dated March 23, 1982. 

4. PRINCIPAL CHANGES. The following principal changes are contained in this 

specification. 

a. The addition of an optional L-847 monitoring contact closure feature. 

b. The addition of an optional L-847 door interlock switch. 

c. The "High-Voltage Contact" cycle switching test was changed from 5,000 cycles 

to 10,000 cycles. 

5. METRIC UNITS. To promote an orderly transition to metric units, this specification 

includes both English and metric dimensions. The metric conversions may not be exact 

equivalents, and until an official changeover to metric units is effective, the English 

dimensions will govern. 

David L. Bennett 

Director Airport Safety and Standards
AC 150/5345-5B 

1. SCOPE AND CLASSIFICATION. 

1.1 Scope. This specification covers the requirements for a circuit selector switch to 

be used for switching the output of a constant current regulator (CCR) to one or more 

series lighting loops.

1.2 Classification. This specification covers four types, two classes, and two sizes of 

circuit selector switches:

1.2.1 Type. This specification covers circuit selector switches of the following 

types:

Type L-847-1 One circuit control 

Type L-847-2 Two circuit control 

Type L-847-3 Three circuit control 

Type L-847-4 Four circuit control 

1.2.2 Classes. This specification covers circuit selector switches of the following 

classes: 

 

Class A Designed for indoor installations 

Class B Designed for outdoor installations 

1.2.3 Ratings. This specification covers circuit selector switches of the following 

ratings: 

Rating 1 Designed for 6.6 ampere, 5,000 volt circuits 

Rating 2 Designed for 20 ampere, 5,000 volt circuits 

2. APPLICABLE DOCUMENTS. 

2.1 General. The following documents, of the issue in effect on the date of 

application for qualification, form part of this specification and are applicable to the 

extent specified herein. 

2.2 Federal Aviation Administration (FAA) Documents. 

2.2.1 FAA Standard.

FAA-STD-012a Paint Systems for Equipment 

 

 FED-STD-595 Colors Used in Government Procurement 

2 
 AC 150/5345-5B 

 - 

Copies of FAA Standards may be obtained from: 

Federal Aviation Administration 

ATO-W CM - NAS Documentation Control Center 

800 Independence Avenue, SW 

Washington, DC 20591 

Phone: (202) 548-5502 

Fax: (202) 548-5501 

Website: http://www.faa.gov/cm/dcc/ 

2.2.2 FAA Advisory Circular.

AC 150/5345-53 Airport Lighting Equipment Certification Program 

Copies of FAA ACs may be obtained from: 

Department of Transportation 

General Services Division 

M-45 

Washington, DC 20590 

Phone: (202) 267-3115, -3161, and -8329 

Website: 

http://www.faa.gov/airports_airtraffic/airports/resources/advisory_circulars/

2.3 Military Standard. 

MIL-STD810C Environmental Test Methods 

Copies of Military Standards and Specification Publications may be obtained from: 

DAPS/DODSSP 

Building 4, Section D 

700 Robins Avenue 

Philadelphia, PA 19111-5094 

Phone: (215) 697-2179 

Fax: (215) 697-1460 

Website: http://dodssp.daps.dla.mil/

3 
AC 150/5345-5B 

3. REQUIREMENTS. 

3.1 General Functional Requirements. The circuit selector switch(es) must be 

capable of switching the output of a constant current regulator to one or more series 

lighting circuits (loops), as illustrated in figure 1. The selector switch must be 

controllable locally or from a remote location. External control switches for remote 

operation are to be supplied by others. 

3.2 Environmental Requirements. The circuit selector switch(es) must be designed 

for operations under the following environmental conditions: 

a. An ambient temperature range of -40° F (-40° C) to + 131° F (+55° )C 

b. A pressure altitude range of sea level to 10,000 feet (3,000 m). 

c. A relative humidity of up to 100 percent from sea level to 10,000 feet 

(3,000 m) at an ambient temperature of + 131° F (+55° )C -. 

 

3.3 Enclosures. All components must be mounted in an enclosure with a hinged 

access door capable of being padlocked. Class A selector switch enclosures must be 

designed for wall mounting and be equal to a National Electrical Manufacturers 

Association (NEMA) type 1. Class B selector switch enclosures must be designed to 

allow bottom mounting by means of a 2-inch conduit and be equal to a NEMA type 4. All 

external electrical wiring is to enter the enclosure through conduit. The size of the 

enclosure must be held to a minimum consistent with good design practices. All highvoltage connections must be made behind a dead front panel so as to be inaccessible 

when the enclosure door is opened to allow local control operations. The enclosure must 

be painted in accordance with the applicable section of FAA-STD-012a. Class B 

enclosures must be painted with aviation orange paint # 12197 per FED-STD-595. 

3.4 High-Voltage Contacts. The circuits must be switched through a series of highvoltage contacts as shown in figure 1. When a circuit is to be energized, the normally 

open contacts close first, followed by the opening of the normally closed contact across 

the constant current regulator input to the switch. The reverse procedure is followed when 

de-energizing the circuit. The contacts must be rated to interrupt a 6.6-ampere circuit for 

the Rating 1 switch and a 20-ampere circuit for the Rating 2 switch from a constant 

current regulated power source having a circuit voltage of up to 5,000 volts. After 10,000 

cycles of switching, the assembly under load at rated current, the contact resistance of the 

relay switches must not exceed 0.1 ohm. Contact resistance is to be measured at rated 

current by voltage drop or a milli-ohm meter. All relay/contactor technologies (air, 

vacuum type, etc.) must not become pitted after cycle testing to the extent of releasing 

smoke or causing fire. 

a. An optional monitoring contact closure for each L-847 output may be 

specified, which closes dry contacts for any L-847 output that is activated. 

4 
 AC 150/5345-5B 

 - 

3.5 Switches. Switches must be provided to permit remote or local control and to 

make circuit selections. The control switch must provide an OFF, REMOTE, and 

LOCAL function and be so marked. A switch with the capacity to provide local circuit 

selection of 1, 2, 3, or 4 lighting loops, according to circuit selector switch type, must 

have markings of Sl, S2, S3, and S4 as appropriate. The control switch must function as 

follows: 

a. When the control switch is in the REMOTE position, the internal control 

circuitry must allow single or multiple circuit selection to be made from a 

remote location. 

b. When the control switch is in the OFF position, the input from the constant 

current regulator is short-circuited and unavailable for the lighting circuits. 

c. When the control switch is in the LOCAL position, lighting circuit selections 

can be made locally. 

d. An optional door interlock switch may be specified that de-energizes the 

output of all constant current regulators when the L-847 door is opened. 

3.6 Terminals. Suitable terminals must be provided for the high-voltage connections 

from the constant current regulator and to the lighting circuits. Terminals or a terminal 

strip must be provided for the control connections. The terminals must be marked as 

follows: 

a. The input terminals for connections from the constant current regulator must 

be labeled "Rl" and "R2." 

b. The output terminals for the lighting circuit(s) must be labeled "Loop 1, Loop 

2", etc. 

c. The terminals provided for control circuits must be labeled as follows: "L" 

and "LN" for 120 AC input voltage OR 24/48 volts DC input voltage; "CR, C, 

Cl", etc. for remote control switch(es). 

Note: Alternate control signals must be appropriately labeled. 

3.7 Assembly. All wire used must have copper conductors of adequate current 

carrying capacity with insulation suitable for the working voltages encountered. Wires 

must be properly trained and cabled. If printed circuit boards are used, they must be 

easily removable for servicing or replacement. The switch assembly must be constructed 

so parts will not work loose during normal operations. 

3.8 Nameplate. A nameplate, permanently and legibly filled in with at least the 

information listed below, must be securely attached to the outside of the enclosure. 

5 
AC 150/5345-5B 

CIRCUIT SELECTOR SWITCH 

Manufacturer's name 

Type_______, Rating_____, Class 

3.9 Equipment Instruction Manual. A parts list with installation, maintenance, and 

repair instructions must be furnished with each assembly. Schematic drawings and 

necessary illustrations must be provided to indicate clearly the method of installation and 

the identity and location of all component parts to facilitate field repairs. 

4. QUALITY ASSURANCE PROVISIONS.

4.1 Qualification Procedures. Procedures for obtaining qualification approval for 

equipment to be furnished for Federal grant assistance programs at airports are contained 

in the current edition of AC 150/5345-53, Airport Lighting Equipment Certification 

Program. 

4.2 Qualification Tests. All tests contained in paragraph 4.4 are applicable for 

qualification. 

4.3 Production Tests. The following tests are applicable for all production units: 

4.4.3, 4.4.4, and 4.4.6. 

4.4 Tests.

4.4.1 Temperature-Altitude. The test must be in accordance with Procedure I, 

Method 504.1, of MIL-STD-810C for equipment in Category 2. The equipment must be 

tested at atmospheric pressures corresponding to sea level and 10,000 feet (3,000 m) 

altitude at both -67°F (-55° C) and +131°F (+55° C). Make the following step 

substitutions to Table 504.1-11, Category 2, for this test: 

Table 1. Specifications for Temperature and Altitude Testing 

STEP 1a 1b 2 3 6 7 10 

Temp (°F) 77 -67 -67 -67 131 131 131 

(°C) 25 -55 -55 -55 55 55 55 

Alt (ft) 10,000 Site Site 10,000 Site Site 10,000 

Time (hr) 1 4 -- -- 16 # 

# - Until temperature stabilizes 

4.4.2 Humidity. The test must be in accordance with Procedure I, Method 507.1, 

of MIL-STD-810C except that a total of two complete cycles (48 hours) will be required. 

4.4.3 Examination. Each assembly must be inspected to assure compliance with 

the requirements specified herein with respect to materials, workmanship, and marking. 

6 
 AC 150/5345-5B 

 - 

4.4.4 Dielectric. Each assembly must withstand the following alternating current 

voltage for one minute without failure: 

a. High-voltage input and output bushings to ground, 11,000 volts. 

b. Control circuit to ground, 1,500 volts. 

4.4.5 Load Test. The circuit selector switch must be subjected to an operational 

test to demonstrate that the equipment will meet the requirements of paragraph 3.4. 

Rating 1 equipment must be tested by switching a fully loaded circuit of a 30 kW 

constant current regulator. Rating 2 equipment must be tested by switching a fully loaded 

circuit of a 70 kW constant current regulator. Multiple circuit selector switches must be 

tested with one circuit loaded and the others short-circuited during the test. 

4.4.6 Operation. Each assembly must be tested to verify that the remote control 

circuit, the local control circuit, and the relay switches operate satisfactorily. 

Note: Alternate control signals must be appropriately labeled. 

7 
AC 150/5345-5B 

(-) (+)

(-) (+)

Note: Alternate control signals must 

be appropriately labeled. 

8 
 AC 150/5345-5B 

 - 

This page intentionally left blank. 

9