Metal Oxide Varistor (MOV)
■CHARACTERISTICS
High performance transient voltage suppression
Short response time to surge voltage
Low standby power dissipation
Excellent clamping characteristics
High performance withstanding surge currents
High reliability
UL, CSA, VDE and CQC recognized
■APPLICATIONS
Surge protection in:
Consumer electronics
Industrial electronics
Communication electronics
Measuring and controlling systems
Electronic home appliances
Protection against surges induced by lighting striking incoming
power lines.
Suppression of surges caused by switching inductive loads such
as transformers, relays and coils.
Protection of rectification diodes, SCRs, power transistors,
semiconductor devices, etc.
■DEFINITION OF VARISTOR TERMS
Rated RMS Voltage, Rated DC Voltage :
The maximum designated values of power system voltage
that may be applied continuously between the terminals of a
device.
Varistor Voltage :
Test characteristic that is used to classify varistors by type.
A test current of 1mA DC is typically used to determine
varistor voltage classification type. Varistor voltage clamping
characteristics can be defined at various test levels.
Rated Peak Single Pulse Transient Current :
Maximum surge current, 8/20 µs waveform which a varistor is
rated to withstand for a single surge.
Rated Single Pulse Transient Energy :
Maximum allowable energy for a single impulse (see specified
waveforms).
Maximum Clamping Voltage :
Measured peak voltage across the device terminals when
a current impulse of specified amplitude and waveform is
conducted through the varistor.
Typical Capacitance :
Typical capacitance values are measured at a test frequency
of 1kHz. Capacitance values are only for reference purpose
only, not subject to outgoing inspection.
■GENERAL CHARACTERISTICS
Storage Temperature : –55˚C to +125˚C
Operating Surface Temperature : 125˚C
Operating Ambient Temperature : –55˚C to +85˚C (without
derating)
Maximum Voltage-Temperature Coefficient : < –0.05% / ˚C
Insulation Resistance : 1000 Mega-ohm minimum
Hi Pot (Leads To Case, 1 Min.) : 2500 VDC
Typical Response Time : <15 Nero-seconds
Epoxy Rating : 94V-0
Current / Energy Derating (>85˚C ) : –2.5% / ˚C
DC Leakage Current : 200µA maximum (at rated DC working
voltage )
Solderability : MIL-STD-202F
Power Dissipation Ratings(P, in-watts) :
Disc Size 11Vac~40Vac 50Vac~680Vac
5mm 0.01 0.15
7mm 0.02 0.25
10mm 0.05 0.4
14mm 0.1 0.6
18mm — 0.8
20mm 0.2 1.0
25mm — 1.2
32mm — 1.6
34mm(single) — 2.1
34mm(dual) — 2.73
40mm — 2.1
53mm — 2.5
All definitions are according to IEEE specifications C62.33.
■ENERGY DERATING VERSUS TEMPERATURE ■PEAK CURRENT PER PULSE VERSUS PULSE
DURATION
Number of
Pulses on Order
From 100 %
Respectively :
1 Pulse
10 Pulses
102 Pulses
103 Pulses
104 Pulses
105 Pulses
106 Pulses
2