86
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Varistor Products
High Energy Industrial
DA/DB Varistor Series
The DA and DB Series transient surge suppressors are heavy-duty
industrial metal-oxide varistors designed to provide surge protection for
motor controls and power supplies used in oil-drilling, mining, and trans-
portation equipment.
These UL-recognized varistors have identical ratings and specifications
but differ in case construction to provide flexibility in equipment designs.
DA series devices feature rigid terminals to insure secure wire contacts.
Both the DA and DB series feature improved creep and strike distance
capability to minimize breakdown along the package surface design that
provides complete electrical isolation of the disc subassembly.
See DA/DB Series Device Ratings and Specifications table for part
number and brand information.
Features
High Energy Absorption Capability
WTM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Up To 1050J
Wide Operating Voltage Range
VM(AC)RMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .130V to 750V
Screw Terminals (DA Series),
Quick Connect Push-On Connectors (DB Series)
Case Design Provides Complete Electrical Isolation of
Disc Subassembly
40mm Diameter Disc
No Derating Up to 85
o
C Ambient
AGENCY APPROVALS:
Recognized under the components program of
Underwriters Laboratories.
AGENCY FILE NUMBERS:
UL E75961.
DB SERIES
DA SERIES
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Varistor Products
2
V
ARIST
OR
PR
ODUCTS
High Energy Industrial
DA/DB Varistor Series
Absolute Maximum Ratings
For ratings of individual members of a series, see Device Ratings and Specifications chart
Continuous:
Steady State Applied Voltage:
AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 to 750
V
DC Voltage Range (VM(DC)) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175 to 970
V
Transient:
Peak Pulse Current (ITM)
For 8/20s Current Wave (See Figure 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40,000
A
Single Pulse Energy Range
For 2ms Current Square Wave (WTM). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 to 1050
J
Operating Ambient Temperature Range (TA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 85
o
C
Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to 125
o
C
Temperature Coefficient (
V) of Clamping Voltage (VC) at Specified Test Current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . <0.01
%/
o
C
Hi-Pot Encapsulation (Isolation Voltage Capability) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5000
V
(Dielectric must withstand indicated DC voltage for one minute per MIL-STD 202, Method 301)
Insulation Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000
M
CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the device
at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Device Ratings and Specifications
DA/DB SERIES
UNITS
PART NUMBER AND
DEVICE BRANDING
MAXIMUM RATINGS (85
o
C)
SPECIFICATIONS (25
o
C)
CONTINUOUS
TRANSIENT
VARISTOR VOLTAGE AT
1mA DC TEST
CURRENT
MAX CLAMP-
ING VOLT V
C
AT 200A
CURRENT
(8/20
s)
TYPICAL
CAPACI-
TANCE
V
RMS
V
DC
ENERGY
(2ms)
PEAK
CURRENT
(8/20
s)
V
M(AC)
V
M(DC)
W
TM
I
TM
MIN
V
N(DC)
MAX
V
C
f = 1MHz
DA
DB
(V)
(V)
(J)
(A)
(V)
(V)
(V)
(V)
(pF)
V131DA40
V131DB40
130
175
270
40000
184
200
228
345
10000
V151DA40
V151DB40
150
200
300
40000
212
240
268
405
8000
V251DA40
V251DB40
250
330
370
40000
354
390
429
650
5000
V271DA40
V271DB40
275
369
400
40000
389
430
473
730
4500
V321DA40
V321DB40
320
420
460
40000
462
510
561
830
3800
V421DA40
V421DB40
420
560
600
40000
610
680
748
1130
3000
V481DA40
V481DB40
480
640
650
40000
670
750
825
1240
2700
V511DA40
V511DB40
510
675
700
40000
735
820
910
1350
2500
V571DA40
V571DB40
575
730
770
40000
805
910
1000
1480
2200
V661DA40
V661DB40
660
850
900
40000
940
1050
1160
1720
2000
V751DA40
V751DB40
750
970
1050
40000
1080
1200
1320
2000
1800
NOTE: Average power dissipation of transients not to exceed 2.0W.
1: Peak current applies to applications rated up to 115V . Peak Current is 30kA for applications greater than 115V .
2: Peak current applies to applications rated up to 132V . Peak Current is 30kA for applications greater than 132V .
RMS
RMS
RMS
RMS
1
2
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Varistor Products
High Energy Industrial
DA/DB Varistor Series
Power Dissipation Ratings
Should transients occur in rapid succession, the average power dissipa-
tion required is simply the energy (watt- seconds) per pulse times the
number of pulses per second. The power so developed must be within the
specifications shown on the Device Ratings and Specifications table for
the specific device. Furthermore, the operating values need to be derated
at high temperatures as shown in Figure 1. Because varistors can only
dissipate a relatively small amount of average power they are, therefore,
not suitable for repetitive applications that involve substantial amounts of
average power dissipation.
FIGURE 1. CURRENT, ENERGY AND POWER DERATING
CURVE
100
90
80
70
60
50
40
30
20
10
0
-55
50
60
70
80
90
100
110
120
130
140
150
PERCENT OF RA
TED
V
ALUE
AMBIENT TEMPERATURE (
o
C)
FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM
100
90
50
10
O
1
T
T
1
T
2
TIME
PERCENT OF PEAK V
ALUE
O
1
= Virtual Origin of Wave
T = Time From 10% to 90% of Peak
T
1
= Virtual Front time = 1.25 t
T
2
= Virtual Time to Half Value (Impulse Duration)
Example: For an 8/20
s Current Waveform:
8
s = T
1
= Virtual Front Time
20
s = T
2
= Virtual Time to Half Value
Transient V-I Characteristics Curve
FIGURE 3. CLAMPING VOLTAGE FOR V131DA40, V131DB40 - V751DA40, V751DB40
200
6,000
5,000
4,000
3,000
1,000
900
800
700
600
500
400
300
10
-2
10
-1
10
0
10
1
10
2
10
3
10
4
10
5
MAXIMUM CLAMPING VOLTAGE
DISC SIZE 40mm
130 TO 750 VM(AC) RATING
T
A
= -55
o
C to 85
o
C
V421DA/DB40
V151DA/DB40
V751DA/DB40
MAXIMUM PEAK
V
O
L
TS (V)
PEAK AMPERES (A)
V131DA/DB40
V321DA/DB40
V271DA/DB40
V251DA/DB40
V511DA/DB40
V481DA/DB40
V571DA/DB40
V661DA/DB40
2,000
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Varistor Products
2
V
ARIST
OR
PR
ODUCTS
High Energy Industrial
DA/DB Varistor Series
Pulse Rating Curves
NOTE: If pulse ratings are exceeded, a shift of VN(DC) (at specified current) of more than 10% could result.This type of shift, which normally results in a decrease of VN(DC),
may result in the device not meeting the original published specifications, but it does not prevent the device from continuing to function, and to provide ample protection.
FIGURE 5. SURGE CURRENT RATING CURVES FOR
V131DA40, V131DB40 - V751DA40, V751DB40
DISC SIZE 40mm
V131DA40 - V751DA40
50,000
20,000
10,000
5,000
2,000
1,000
500
200
100
50
20
10
20
100
1,000
10,000
SURGE CURRENT (A)
IMPULSE DURATION (
s)
V131DB40 - V751DB40
2
1
INDEFINITE
10
4
10
3
10
2
10
5
10
6
10
DA SERIES
Dimensions in millimeters and (inches).
A
4.3mm
(0.170)
15mm (0.59)
"A"
DIMENSION:
FILISTER HEAD SCREW - 51mm (2.01)
PAN HEAD SCREW - 53mm (2.09)
23mm
1mm
(0.90
0.04)
57mm
(2.24)
67mm
(2.64)
62mm
(2.44)
M4 INTERNATIONAL
THREAD
4.5mm (0.18)
Mechanical Dimensions
DB SERIES
60.3
(2.37)
44.45
0.75
(1.75
0.03)
46.8
(1.84)
25.4
0.75
(1.00
0.03)
ALL DIMENSIONS ARE MAXIMUM
EXCEPT WHERE NOTED
HOLES 0.23 THRU
BORE 0.370 x 0.370 DP
12.7
(0.50)
6.60
(0.26)
2 HOLES
6.60
(0.26)
41
(1.61)
40.5
(1.6)
1.6
(0.06)
23
(0.90)
12.7
(0.50)