ASTM F1669M-96(2002)

Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]

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 the standard. The values given in parentheses are for information only.
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Jun-1996
• ICS: 47.020.60 - Electrical equipment of ships and of marine structures
• Technical Committee: F25 - Ships and Marine Technology
• Drafting Committee: F25.10 - Electrical

Relations

• Replaced By: ASTM F1669M-96(2007) - Standard Specification for Insulation Monitors for Shipboard Electrical Systems [Metric]
• Effective Date: 01-May-2007

Standards Content (Sample)

An American National Standard
Designation: F 1669M – 96 (Reapproved 2002)
METRIC
Standard Specification for
Insulation Monitors for Shipboard Electrical Systems
[Metric]
This standard is issued under the fixed designation F 1669M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 2.3 Military Standard:
MIL-STD-1399 (NAVY) Section 300A Interface Standards
1.1 This specification covers two (2) types of electrical
for Shipboard Systems; Electrical Power, Alternating
system insulation monitoring devices.
Current
1.1.1 Type I is an ac device intended as a permanently
installed unit for use in the detection of ohmic insulation faults
3. Terminology
to ground in active ac ungrounded electrical systems up to
3.1 Definitions of Terms Specific to This Standard:
1000 VAC, having dc components up to 1500 VDC.
3.1.1 ac or dc ungrounded electrical system, n—a system
1.1.2 Type II is a dc device intended as a permanently
that has no intentional connection to ground and can continue
installed unit for use in the detection of ohmic insulation faults
to perform normally if one conductor becomes connected to
to ground in dc ungrounded electrical systems up to 1500
ground.
VDC.
3.1.2 measuring signal, n—the output signal from the insu-
1.2 Limitations—This specification does not cover devices
lation monitor that is superimposed between the ac or dc
that are intended for operation in ac ungrounded systems
ungrounded system to be monitored and ground.
without dc components.
3.1.3 response value, n—the adjustable or preset set-point
1.3 The values stated in SI units are to be regarded as the
value of the system insulation resistance at which an insulation
standard. The values given in parentheses are for information
monitor will provide an alarm indication.
only.
3.1.4 system leakage capacitance, n—the total capacitance
1.4 The following precautionary caveat pertains only to the
to ground of the system including all connected consumers.
test methods portion, Section 7 of this specification: This
3.1.5 touch voltage, n—the voltage appearing during an
standard does not purport to address all of the safety concerns,
insulation fault, between simultaneously accessible parts. This
if any, associated with its use. It is the responsibility of the user
term is used only in connection with protection against indirect
of this standard to establish appropriate safety and health
human contacts, that is, no direct human contact with a live
practices and determine the applicability of regulatory limita-
conductor. The International Electrotechnical Commission
tions prior to use.
(IEC) limits the maximum prospective touch voltage which can
2. Referenced Documents be maintained indefinitely to 50 VAC rms or 120 V ripple-free
dc.
2.1 UL Standard:
UL STD 840 Insulation Coordination Including Clearances
4. Ordering Information
and Creepage Distances for Electrical Equipment
4.1 Orders for monitoring devices under this specification
2.2 IEC Standards:
3 shall state the following information:
IEC 255-5 Insulation Tests for Electrical Relays
4.1.1 Type and quantity.
IEC 364-4-41 Electrical Installations of Buildings/
3 4.1.2 Nominal system voltage and frequency (for ac sys-
Protection for Safety/Protection Against Electrical Shock
tem).
4.1.3 Input supply voltage.
This specification is under the jurisdiction of ASTM Committee F25 on Ships
4.1.4 Response value/set-point range expressed in K-Ohms.
and Marine Technology and is the direct responsibility of Subcommittee F25.10 in
4.1.5 ASTM designation and year of issue.
Electrical.
4.1.6 System leakage capacitance or data from which an
Current edition approved June 10, 1996. Published August 1996.
Available from Underwriters Laboratories, Inc., 333 Pfingsten Rd., Northbrook,
IL 60062.
3 4
Available from American National Standards Institute (ANSI), 25 W. 43rd St., Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700
4th Floor, New York, NY 10036. Robbins Ave., Philadelphia, PA 19111-5098, Attn: NPODS.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F 1669M
estimate of its magnitude can be determined. 6.8 Built-In Display of Insulation Resistance—If provisions
4.1.7 Special requirements such as Test/Reset buttons, ohm- are made to indicate (display) the current insulation resistance
meters, visual indicators, memory fault retention, and so forth. level, then the manufacturer shall provide information as to the
accuracy of this indication during normal operating conditions.
5. Materials and Manufacturing Methods
6.9 Clearance and Creepage Distances—The insulation
monitor shall have protective spacings through air (clearance)
5.1 The materials and manufacturing methods used shall be
and over surface (creepage) as stated in UL STD 840 for the
such that the resulting products will conform to the properties
intended maximum circuit voltage.
and characteristics prescribed in this specification.
6.10 Impulse Voltage Withstand Tests—The insulation
6. Performance Requirements
monitor shall meet the IEC 255-5 Class III Impulse Voltage
Withstand Test Requirements.
6.1 Response of Insulation Monitor to a Step Input—The
insulation monitor measures the combined parallel resistance
7. Operating Environment
to ground from all power or circuit conductors. The time to
7.1 The insulation monitor shall reliably function over an
respond to a step change in the actual resistance to a value less
ambient temperature range of 0 to 50°C (32 to 122°F) and at a
than or equal to 50 % of the desired response value shall be
relative humidity of 95 %. Storage temperatures of −20 to
governed by the expression:
+60°C (−4 to 140°F) shall not damage the insulation monitor.
t ~s! # 100 1 40 ~R 3 C ! (1)
I s
8. Test Methods
8.1 Conformance Test—Conformance testing of insulation
where
R = internal resistance of monitor, ohm, and monitors shall be performed to confirm that the response
I
C = total system capacitance, farad. tolerances stipulated are not exceeded and that the require-
s
For example, ments of Section 6 are met.
8.1.1 Response Value Tests—The measuring devices used
t 5 124sifR 5 120 000 ohm and C 5 5 3 10
I s
for testing shall enable a slow stepless or step-by-step change
farad.
of the simulated insulation resistance and shall allow the
6.2 Measuring Signal Voltage Limits—The peak value of connection of artificial system leakage capacitances. To simu-
the measuring signal shall under all operating conditions be late the system leakage capacitance, capacitors with an isola-
limited to a magnitude deemed acceptable by applicable safety
tion resistance of 100 times the desired response value and with
standards for the intended use. The peak value of the measuring a tolerance of +10 % maximum shall be used. On testing, the
signal shall be less than the touch voltage limits: 120 VDC
resistance shall be decreased slowly and the insulation moni-
ripple-free and 50 VAC rms. tor’s response shall be observed. For testing the response value,
6.3 Internal Impedance and Internal Resistance—The ac the test arrangement with its insulation resistance level and its
internal impedance and dc internal resistance shall be at least own capacitance must be considered.
30 ohms per volt nominal system voltage but in either case 8.1.1.1 An insulation monitor with adjustable response shall
shall not be less than 12 K-Ohms. be tested at the beginning, mid and end points of its range.
6.4 Response Tolerance—The response tolerance of the These tests sh
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