ASTM F1669M-12(2018)
(Specification)Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]
Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]
ABSTRACT
This specification covers insulation monitoring devices for stripboard electrical systems. Materials covered by this specification include Type I (ac device) and Type II (dc device) electrical system insulation monitoring devices used in the detection of ohmic insulation faults to ground in either active ac ungrounded electrical systems with dc components (Type I) or dc ungrounded electrical systems (Type II). However, devices used in ac ungrounded systems without dc components are not included. The devices shall undergo conformance and routine tests to ensure that the device meets the requirements specified. Conformance tests shall included testing of response time, peak voltage, input impedance or resistance, built-in meters, and impulse voltage withstand capabilities, whereas routine tests shall include testing of response value, self-test function, built-in meters, and voltage.
SCOPE
1.1 This specification covers two (2) types of electrical system insulation monitoring devices.
1.1.1 Type I is an AC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in active AC ungrounded electrical systems up to 1000 VAC, having DC components up to 1500 VDC.
1.1.2 Type II is a DC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in DC ungrounded electrical systems up to 1500 VDC.
1.2 Limitations—This specification does not cover devices that are intended for operation in AC ungrounded systems without DC components.
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are included for information only and are not considered standard.
1.4 The following precautionary caveat pertains only to the test methods portion, Section 7 of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
- Status
- Published
- Publication Date
- 31-Mar-2018
- Technical Committee
- F25 - Ships and Marine Technology
- Drafting Committee
- F25.10 - Electrical
Relations
- Effective Date
- 01-Apr-2018
Overview
ASTM F1669M-12(2018) is a standard specification developed by ASTM International for insulation monitors used in shipboard electrical systems. This standard provides requirements for the construction, testing, performance, and marking of insulation monitoring devices specifically designed to detect ohmic insulation faults to ground in ungrounded AC or DC shipboard electrical systems. Such monitoring devices are critical for ensuring electrical safety and operational reliability by alerting operators to insulation degradation before it leads to hazardous faults or system failures.
The standard covers both Type I (AC device) for use in ungrounded active AC electrical systems with DC components and Type II (DC device) for ungrounded DC systems. It establishes test procedures to ensure that insulation monitors meet strict performance, safety, and reliability requirements, reflecting internationally recognized principles on standardization.
Key Topics
Types of Insulation Monitors
- Type I: Designed for permanent installation in active, ungrounded AC systems (up to 1000 VAC) with DC components (up to 1500 VDC).
- Type II: Designed for permanent installation in ungrounded DC systems up to 1500 VDC.
Performance Requirements
- Fast response to insulation resistance changes.
- Proper functioning over a range of system voltages (0–115% nominal) and frequency (50–400 Hz for AC systems).
- Built-in or wired self-test capabilities to verify correct operation.
- Ability to trigger external alarms or provide remote status indication.
- Peak measurement voltages within specified safety limits.
Testing and Quality Assurance
- Conformance Tests: Assess response time, voltage handling, input impedance, meter accuracy, and impulse voltage withstand capability.
- Routine Tests: Validate operational readiness, self-test function, and meter accuracy.
- Requirements for hardware characteristics like clearance and creepage distances, per UL STD 840, and impulse voltage standards, per IEC 255-5.
Marking and Documentation
- Manufacturer name, model, electrical ratings, connection diagrams, test values, and serial numbers must be clearly included.
- Equipment manuals must detail the installation, operation, and performance characteristics.
Limitations
- The standard does not apply to insulation monitors for AC ungrounded systems without DC components.
Applications
ASTM F1669M-12(2018) insulation monitors are integral to the safety and reliability of shipboard electrical systems. Their typical applications include:
- Marine electrical distribution systems: Facilitating early detection of insulation degradation in complex vessel power systems.
- Ungrounded AC/DC systems: Providing real-time monitoring in systems requiring continuous operation even with single insulation faults.
- Safety-critical operations: Enabling faster response and preventive maintenance to avoid fire risk and electrical hazards in commercial and naval ships.
- Regulatory compliance: Assisting shipowners and operators in meeting international marine safety and electrical standards.
Related Standards
- UL STD 840: Insulation Coordination Including Clearances and Creepage Distances for Electrical Equipment
- IEC 255-5: Insulation Tests for Electrical Relays
- IEC 364-4-41: Electrical Installations of Buildings - Protection for Safety/Protection against Electric Shock
- MIL-STD-1399(NAVY) Section 300A: Interface Standards for Shipboard Systems; Electrical Power, Alternating Current
These related standards complement ASTM F1669M-12(2018) by establishing safety benchmarks, testing methods, and installation guidelines relevant to insulation monitoring and electrical system design on ships.
Keywords: insulation monitor, shipboard electrical systems, ohmic insulation fault, ungrounded AC/DC systems, ASTM F1669M-12, electrical safety, marine standards, insulation monitoring device, conformance testing, marine electrical compliance
Buy Documents
ASTM F1669M-12(2018) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]
Get Certified
Connect with accredited certification bodies for this standard

DNV
DNV is an independent assurance and risk management provider.

Lloyd's Register
Lloyd's Register is a global professional services organisation specialising in engineering and technology.

FSC International
Forest Stewardship Council certification.
Sponsored listings
Frequently Asked Questions
ASTM F1669M-12(2018) is a technical specification published by ASTM International. Its full title is "Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]". This standard covers: ABSTRACT This specification covers insulation monitoring devices for stripboard electrical systems. Materials covered by this specification include Type I (ac device) and Type II (dc device) electrical system insulation monitoring devices used in the detection of ohmic insulation faults to ground in either active ac ungrounded electrical systems with dc components (Type I) or dc ungrounded electrical systems (Type II). However, devices used in ac ungrounded systems without dc components are not included. The devices shall undergo conformance and routine tests to ensure that the device meets the requirements specified. Conformance tests shall included testing of response time, peak voltage, input impedance or resistance, built-in meters, and impulse voltage withstand capabilities, whereas routine tests shall include testing of response value, self-test function, built-in meters, and voltage. SCOPE 1.1 This specification covers two (2) types of electrical system insulation monitoring devices. 1.1.1 Type I is an AC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in active AC ungrounded electrical systems up to 1000 VAC, having DC components up to 1500 VDC. 1.1.2 Type II is a DC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in DC ungrounded electrical systems up to 1500 VDC. 1.2 Limitations—This specification does not cover devices that are intended for operation in AC ungrounded systems without DC components. 1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are included for information only and are not considered standard. 1.4 The following precautionary caveat pertains only to the test methods portion, Section 7 of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ABSTRACT This specification covers insulation monitoring devices for stripboard electrical systems. Materials covered by this specification include Type I (ac device) and Type II (dc device) electrical system insulation monitoring devices used in the detection of ohmic insulation faults to ground in either active ac ungrounded electrical systems with dc components (Type I) or dc ungrounded electrical systems (Type II). However, devices used in ac ungrounded systems without dc components are not included. The devices shall undergo conformance and routine tests to ensure that the device meets the requirements specified. Conformance tests shall included testing of response time, peak voltage, input impedance or resistance, built-in meters, and impulse voltage withstand capabilities, whereas routine tests shall include testing of response value, self-test function, built-in meters, and voltage. SCOPE 1.1 This specification covers two (2) types of electrical system insulation monitoring devices. 1.1.1 Type I is an AC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in active AC ungrounded electrical systems up to 1000 VAC, having DC components up to 1500 VDC. 1.1.2 Type II is a DC device intended as a permanently installed unit for use in the detection of ohmic insulation faults to ground in DC ungrounded electrical systems up to 1500 VDC. 1.2 Limitations—This specification does not cover devices that are intended for operation in AC ungrounded systems without DC components. 1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are included for information only and are not considered standard. 1.4 The following precautionary caveat pertains only to the test methods portion, Section 7 of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
ASTM F1669M-12(2018) is classified under the following ICS (International Classification for Standards) categories: 47.020.60 - Electrical equipment of ships and of marine structures. The ICS classification helps identify the subject area and facilitates finding related standards.
ASTM F1669M-12(2018) has the following relationships with other standards: It is inter standard links to ASTM F1669M-12. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
ASTM F1669M-12(2018) is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F1669M −12 (Reapproved 2018) An American National Standard
Standard Specification for
Insulation Monitors for Shipboard Electrical Systems
(Metric)
This standard is issued under the fixed designation F1669M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
1.1 This specification covers two (2) types of electrical
2.1 UL Standard:
system insulation monitoring devices.
UL STD840Insulation Coordination Including Clearances
1.1.1 Type I is an AC device intended as a permanently
and Creepage Distances for Electrical Equipment
installed unit for use in the detection of ohmic insulation faults
2.2 IEC Standards:
to ground in active AC ungrounded electrical systems up to
IEC255-5Insulation Tests for Electrical Relays
1000 VAC, having DC components up to 1500 VDC.
IEC 364-4-41 Electrical Installations of Buildings/
1.1.2 Type II is a DC device intended as a permanently
Protection for Safety/Protection Against Electrical Shock
installed unit for use in the detection of ohmic insulation faults 4
2.3 Military Standard:
to ground in DC ungrounded electrical systems up to 1500
MIL-STD-1399(NAVY) Section 300A Interface Standards
VDC.
for Shipboard Systems; Electrical Power, Alternating
1.2 Limitations—This specification does not cover devices
Current
that are intended for operation in AC ungrounded systems
3. Terminology
without DC components.
3.1 Definitions of Terms Specific to This Standard:
1.3 The values stated in SI units are to be regarded as
3.1.1 AC or DC ungrounded electrical system, n—a system
standard. The values given in parentheses after SI units are
that has no intentional connection to ground and can continue
included for information only and are not considered standard.
to perform normally if one conductor becomes connected to
1.4 The following precautionary caveat pertains only to the
ground.
test methods portion, Section 7 of this specification: This
3.1.2 measuring signal, n—the output signal from the insu-
standard does not purport to address all of the safety concerns,
lation monitor that is superimposed between the AC or DC
if any, associated with its use. It is the responsibility of the user
ungrounded system to be monitored and ground.
of this standard to establish appropriate safety, health, and
environmental practices and determine the applicability of
3.1.3 response value, n—the adjustable or preset set-point
regulatory limitations prior to use.
valueofthesysteminsulationresistanceatwhichaninsulation
1.5 This international standard was developed in accor-
monitor will provide an alarm indication.
dance with internationally recognized principles on standard-
3.1.4 system leakage capacitance, n—the total capacitance
ization established in the Decision on Principles for the
to ground of the system including all connected consumers.
Development of International Standards, Guides and Recom-
3.1.5 touch voltage, n—the voltage appearing during an
mendations issued by the World Trade Organization Technical
insulation fault, between simultaneously accessible parts. This
Barriers to Trade (TBT) Committee.
termisusedonlyinconnectionwithprotectionagainstindirect
1 2
This specification is under the jurisdiction ofASTM Committee F25 on Ships Available from Underwriters Laboratories (UL), 333 Pfingsten Rd.,
and Marine Technology and is the direct responsibility of Subcommittee F25.10 in Northbrook, IL 60062-2096, http://www.ul.com.
Electrical. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
Current edition approved April 1, 2018. Published May 2018. Originally 4th Floor, New York, NY 10036, http://www.ansi.org.
approved in 1996. Last previous edition approved in 2012 as F1669M–12. DOI: Available from DLA Document Services, Building 4/D, 700 Robbins Ave.,
10.1520/F1669M-12R18. Philadelphia, PA 19111-5094, http://quicksearch.dla.mil.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1669M − 12 (2018)
human contacts, that is, no direct human contact with a live 6.5 Working Range of System Voltage and Frequency —The
conductor. The International Electrotechnical Commission insulation monitor shall perform as specified when operating
(IEC)limitsthemaximumprospectivetouchvoltagewhichcan with a system voltage of 0–115% nominal over the frequency
be maintained indefinitely to 50 VAC rms or 120 V ripple-free range 50–400 hz.
DC.
6.6 Self-Test—Theinsulationmonitorshallincludeabuilt-in
test device or be equipped with connection provisions for a
4. Ordering Information
separate device that shall be furnished with the equipment
4.1 Orders for monitoring devices under this specification which can verify the proper functioning for the monitor.
shall state the following information:
6.7 Output Relay—The insulation monitor shall have provi-
4.1.1 Type and quantity.
sionsforanexternal(remote)audibleorvisualalarmtooperate
4.1.2 Nominal system voltage and frequency (for AC sys-
when the insulation resistance value falls below the set-point
tem).
value, or a remote indication of the insulation resistance value
4.1.3 Input supply voltage.
of the ungrounded system, or both. Built-in relay contacts for
4.1.4 Response value/set-point range expressed in K-Ohms.
connection to an external alarm shall have a continuous rating
4.1.5 ASTM designation and year of issue.
of at least 4 amperes at 250 VAC. The break capacity shall be
4.1.6 System leakage capacitance or data from which an
at least 2 amps at 250 VAC (0.7 power factor) and 0.3 amps at
estimate of its magnitude can be determined.
120 VDC.
4.1.7 Special requirements such as Test/Reset buttons,
6.8 Built-In Display of Insulation Resistance—If provisions
ohmmeters, visual indicators, memory fault retention, and so
are made to indicate (display) the current insulation resistance
forth.
level,thenthemanufacturershallprovideinformationastothe
accuracyofthisindicationduringnormaloperatingconditions.
5. Materials and Manufacturing Methods
6.9 Clearance and Creepage Distances—The insulation
5.1 The materials and manufacturing methods used shall be
monitor shall have protective spacings through air (clearance)
such that the resulting products will conform to the properties
and over surface (creepage) as stated in UL STD 840 for the
and characteristics prescribed in this specification.
intended maximum circuit voltage.
6.10 Impulse Voltage Withstand Tests—The insulation
6. Performance Requirements
monitor shall meet the IEC 255-5 Class III Impulse Voltage
6.1 Response of Insulation Monitor to a Step Input —The
Withstand Test Requirements.
insulation monitor measures the combined parallel resistance
to ground from all power or circuit conductors. The time to
7. Operating Environment
respond to a step change in the actual resistance to a value less
7.1 The insulation monitor shall reliably function over an
than or equal to 50% of the desired response value shall be
ambient temperature range of 0 to 50°C (32 to 122°F) and at a
governed by the expression:
relativehumidityofupto95%.Storagetemperaturesof−20to
t s # 100140 R 3 C (1)
~ ! ~ !
I s
+60°C (−4 to 140°F) shall not damage the insulation monitor.
where:
8. Test Methods
R = internal resistance of monitor, ohm, and
I
8.1 Conformance Test—Conformance testing of insulation
C = total system capacitance, farad.
s
monitors shall be performed to confirm that the response
For example,
tolerances stipulated are not exceeded and that the require-
t 5 124sifR 5 120000 ohm and C 5 5 310 farad
ments of Section 6 are met.
I s
8.1.1 Response Value Tests—The measuring devices used
6.2 Measuring Signal Voltage Limits—Thepeakvalueofthe
for testing shall enable a slow stepless or step-by-step change
measuringsignalshallund
...
![ASTM F1669M-12(2018) ASTM F1669M-12(2018) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric] - Page 1 preview](https://cdn.standards.iteh.ai/images/100123/9430c9d37c544092a57b64b47da7bc76/small/page1.jpg)
![ASTM F1669M-12(2018) ASTM F1669M-12(2018) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric] - Page 2 preview](https://cdn.standards.iteh.ai/images/100123/9430c9d37c544092a57b64b47da7bc76/small/page2.jpg)
![ASTM F1669M-12(2018) ASTM F1669M-12(2018) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric] - Page 3 preview](https://cdn.standards.iteh.ai/images/100123/9430c9d37c544092a57b64b47da7bc76/small/page3.jpg)
![ASTM F1669M-12(2018) ASTM F1669M-12(2018) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric] - Page 4 preview](https://cdn.standards.iteh.ai/images/100123/9430c9d37c544092a57b64b47da7bc76/small/page4.jpg)
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.
Loading comments...