Panasonic TYPE E User Manual
“ZNR” Transient/Surge Absorbors, Type E, Type CK, SC
– EC129 –
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1.
Precautions for Safety
The “ZNR” Transient/Surge Absorbers (hereafter referred to as “The ZNR Varistors”) may fail in a short-circuit mode
or in an open-circuit mode, when subjected to severe conditions of electrical, environmental and/or me
or in an open-circuit mode, when subjected to severe conditions of electrical, environmental and/or me
chanical
stresses beyond their specifi
ed “Ratings” and specifi
ed “Conditions”, resulting in burnout, fl
aming or glowing in the
worst case.
Following “
Following “
Precautions for Safety” and “Application Notes” shall be taken in your major consideration. If you have
a question about the “Precautions for Handling”, please contact our engineering section or factory.
Precautions for Handling
“ZNR” Transient/Surge Absorbers, Type E
“ZNR” Transient/Surge Absorbers, Type CK, SC
“ZNR” Transient/Surge Absorbers, Type CK, SC
1.1 Operating Conditions
1.1.1 The ZNR Varistors shall not be operated beyond
t h e s p e c i f i e d “ R a t i n g s” a n d “ E nv i ro n m e n t a l
Conditions” in the Catalog or the Specifi
Conditions” in the Catalog or the Specifi
cations to
prevent them from deterioration, breakdown, fl
aming
or glowing.
● The ZNR Varistors shall not be operated exceeding
● The ZNR Varistors shall not be operated exceeding
the specifi
ed “Maximum Allowable Voltage” in the
Catalog or the Specifi cation.
● The ZNR Varistors shall not be subjected to
energy levels above their specifi
ed “Maximum
Energy Ratings” in the Catalog or the Specifi cations.
● In case of application to repeated surge/
overvoltages, the ZNR Varistors shall not be
subjected to surge currents and energy levels
above the specifi
subjected to surge currents and energy levels
above the specifi
ed maximum ratings in “Impulse
Life Rating” in the Catalog or the Specifi cations.
● When surge/overvoltages are intermittently
applied to the ZNR Varistors with short durations,
the devices shall not be operated beyond the
specifi ed “Rated Power” in the Catalog or the
Specifi cations.
the devices shall not be operated beyond the
specifi ed “Rated Power” in the Catalog or the
Specifi cations.
● The ZNR Varistors shall not be operated beyond
the specifi
ed “Operating Temperature Range” in
the Catalog or the Specifi cations.
● It is recommended that the ZNR Varistors, if
not fused, shall be located away from other
combustible components.
combustible components.
1.1.2 The ZNR Varistor shall be operated correctly
under following conditions to prevent Varistors from
causing mechanical damages and ruptures and to
protect human from serious injuries;
● The ZNR Varistors shall not be operated
causing mechanical damages and ruptures and to
protect human from serious injuries;
● The ZNR Varistors shall not be operated
exceeding the specifi
ed “Maximum Allowable
Voltage Ratings” in the Catalog.
● The ZNR Varistors shall not be operated beyond
the “Maximum Peak Current Ratings” in the
Catalog.
Catalog.
● S o me safet y countermeasure such as a
p r o t e c t i v e c a s e c o v e r i n g t h e Va r i s t o r i s
recommended, if necessary.
recommended, if necessary.
1.1.3 When the ZNR Varistors are applied to between
a live part and a metallic chassis of equipment,
following safety countermeasures shall be taken to
following safety countermeasures shall be taken to
protect human from electric shock.
A) The metallic chassis shall be earthed to the
ground.
B) The live part shall be equipped with a protective
cover for preventing electric shock.
2. Application Notes
2.1 Protective Devices for Varistors
2.1.1 The ZNR Varistors shall be protected from serious
accidents due to unexpected physical phenomenor
by following safety countermeasures.
● In case of “Across-the Line Use”, the ZNR
by following safety countermeasures.
● In case of “Across-the Line Use”, the ZNR
Varistors shall be protected by connecting a
ground fault circuit interrupter of fusing in series
to the devices. (See Table 1)
ground fault circuit interrupter of fusing in series
to the devices. (See Table 1)
● In case of “Line to Ground Use”, the short-circuit
of the Varistor may not blow the current type
fuse due to the grounding resistance (between
Line and Ground), which may cause fl
fuse due to the grounding resistance (between
Line and Ground), which may cause fl
aming or
burnout of the devices in the worst case.
Following safety countermeasures (A or B) are
recommended;
A) Connecting a “leakage current circuit breaker” in
recommended;
A) Connecting a “leakage current circuit breaker” in
series to the Varistor to be protected. (See Table
1)
1)
B) Use current type fuses and a thermal type fuse
which are thermally coupled each others. (See
Table 1)
Table 1)
✽ Fuses shall use rated voltages appropriate for circuits.
✽ Finally, confi rm that the secondary disaster does not
occur even if the ZNR mounted on equipment breaks.
✽ Set a thermal fuse to get high thermal conductivity
with ZNR.
Series
ERZC20EK
첸첸첸 ERZC32첸K첸첸첸
ERZVS34C
첸첸첸
ERZC40CK
첸첸첸
Current Fuse
(Line - Line)
10 A max.
20 A max.
20 A max.
Thermal. Fuse
(Line - Ground)
100 to 120 °C 5 A 100 to 120 °C 10 A 100 to 120 °C 10 A
● Recommendation fuse
Apr. 2008
00