139
Introduction
For many customers and applications, toughened glass provides the highest level of performance and long-term security for high voltage insulation. MacLean is pleased to be able to provide our customers toughened glass insulators from stock held at our South Carolina factory. The products have service experience dating back to 1957 with installations in a broad range of operating conditions with more than 300 utilities worldwide at voltages from 15 to 1150kV AC and up to 800kV DC. Insulators are manufactured in two factory locations to insure steady supply and sufficient capacity for even the largest projects. Both plants utilize the same manufacturing process and the same automated ‘Waltek’ equipment for the toughening process with an annual output of more than 14 million pieces.
The products of the two factories comply with the quality management systems of ISO 9001, 14001, and 18001. The products have been subjected to testing in the factory laboratories and international independent test centers to confirm the customer’s requirements and national standards. The toughened glass insulators are tested per ANSI, IEC, CSA and GOST.
Toughened glass has many inherent characteristics that makes it especially suitable for HV, EHV and DC applications:
■ Unlike porcelain or non-ceramic materials, toughened glass insulating material never ages.
■ The binary status (all or none) of TG is desirable for line maintenance. In the event of electrical or mechanical damage, the shell collapses allowing maintenance personnel to easily identify faults visually from the ground without any special instruments or tools
■ TG has 4 times the mechanical impact strength dictated by ANSI (90in/lb) compared to porcelain, which reduces losses due to shell damage during construction and handling
■ Even with the insulating shell absent, the toughened glass stub is guaranteed to retain its mechanical strength, eliminating the chance of line drop due to insulator separation
■ All units are subjected to routine mechanical proof load AND 4 minute electrical flashover test prior to shipment, so the
M&E integrity is guaranteed on every unit shipped.
The current designs are based on 50-year-old operating experience in the field of insulation at the important high-voltage objects in harsh environmental conditions:
■ Standard and FOG profile
■ Ultra-FOG glass insulator profiles
■ Silicone Coated
■ DC insulators
MacLean Toughened Glass Design Details
1. Cap – Cast Iron / Hot dip galvanized
2. Locking Device – Stainless Steel Cotter Pin
3. Toughened Glass Shell
4. Gasket – Interlaying Material
5. Pin – Forged Steel / Hot dip galvanized
6. Alumina Cement
7. Zinc Sleeve – Supplied standard on all MG Insulators
Insulator Markings – permanent markings, as required by
ANSI, are marked both on the Cap and Shell of the insulators.
Markings include MPS logo, M&E Rating, ANSI Class, Plant
MFG ID and Date Code.
© 2016 Copyright MacLean Power Systems
Technical information subject to change without notice

Standard Shell Profile
Features
■ Certified to ANSI C29.2B Standard / CSA / IEC
■ Zinc Sleeve Standard on all MG Insulators
■ Alumina Cement
■
■ Standard Pack = 6 Units / Wirebound Crate
■
400 in-lbs Toughened Glass Mechanical Impact Strength
Silicone Coated Insulators available
Shell Diameter
Catalog Number
ANSI Class
Coupling Type
MECHANICAL
MG523Z
52-3
B
Min. Mechanical
Failing Load
Proof Routine Test
Mech. Load lbs kN lbs kN
20,000
90
10,000
45
DIMENSIONS
Shell Diameter
Coupling Length in / mm 10.0
/ 255 in / mm 5.75
/ 146
Leakage Distance in / mm 13.1
/ 320
ELECTRICAL
MG525Z
52-5
10.0
5.75
13.1
J
30,000
136
15,000
68
/ 255
/ 146
/ 320
MG528Z
52-8
K
40,000
180
20,000
11.0
5.75
15.8
90
/ 280
/ 146
/ 385
Dry Flashover
Wet Flashover
CIFO +
CIFO -
Puncture Voltage
RIV Test Voltage
Max. RIV at 1 MHz
PACKAGING kV kV kV kV kV kV
µV
80
50
125
130
130
10
50
80
50
125
130
130
10
50
Weight / 1
# Units / Wirebound
Weight / Wirebound
# Units / Pallet lbs
Qty lbs
Qty
8.8
6
57
72 / 96
9.3
6
60
72 / 96
Weight / Pallet
Bulk Pack "-SC" lbs
Qty
734 / 962
210
770 / 1010
210
824
144
Weight / Bulk Pack lbs 1900 2000 2000
Notes:
1) For Bulk Pack option, add suffix “-SC” to the catalog number [MG525Z-SC]
2) For Silicone Coated option, add suffix “-SIL” to the catalog number [MG525Z-SIL]
13.6
6
86
54
80
50
125
130
130
10
50
MG5211Z
52-11
K
50,000
222
25,000
111
11.0
6.14
17.5
/ 280
/ 156
/ 428
80
50
140
140
130
10
50
17.4
6
110
54
1040
144
2550
MG300Z
IEC-24
67,400
300
33,700
150
12.6 / 320
7.7 / 195
19.1 / 485
95
55
145
145
130
10
50
25.4
6
158
54
1472
—
—
MG400Z
IEC-28
90,000
400
45,000
200
14.2 / 360
8.1 / 205
21.7 / 550
35.7
6
216
54
1644
—
—
105
60
155
155
130
10
50
© 2016 Copyright MacLean Power Systems
Technical information subject to change without notice 140

141
Number of insulators in the string
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Connectioin Length
Inch
11.50
17.25
23.00
28.75
34.50
40.25
46.00
51.75
57.50
63.25
69.00
74.75
80.50
86.25
92.00
97.75
103.50
109.25
115.00
120.75
126.50
132.25
138.00
143.75
149.50
155.25
161.00
166.75
mm
292
438
584
730
876
1022
1168
1314
1461
1607
1753
1899
2045
2191
2337
2483
2629
2775
2921
3067
3213
3359
3505
3651
3797
3943
4089
4235
Power frequency flashover voltage, kV dry
145
205
270
325
380
435
485
540
590
640
690
735
785
830
875
920
965
1010
1050
1100
1135
1180
1220
1260
1300
1340
1380
1425 wet
90
130
170
215
255
295
335
375
415
455
490
525
565
600
635
670
705
740
775
810
845
880
915
950
985
1015
1045
1080
30 172.50
4382 1460 1110
Notes:
■ Flashover voltages are based on the tests according to ANSI C 29.1.
■ Characteristics are given for the strings without screens and arcing horns.
■ Dry power frequency flashover voltage ±5%
■ Wet power frequency flashover voltage ±10%
■ Critical impulse flashover voltage ±8%
2065
2145
2220
2300
2375
2455
2530
1425
1505
1585
1665
1745
1825
1905
1985
760
845
930
1015
1105
1185
1265
1345
Critical impulse flashover voltage, kV
Positive Negative
220
315
225
320
410
500
595
670
420
510
605
695
1105
1190
1275
1360
780
860
945
1025
2125
2210
2295
2380
2465
2550
2635
1440
1530
1615
1700
1785
1870
1955
2040
© 2016 Copyright MacLean Power Systems
Technical information subject to change without notice

Number of insulators in the string
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Connectioin Length
Inch
12.28
18.43
24.57
30.71
36.85
42.99
49.13
55.28
61.42
67.56
73.70
79.84
85.98
92.13
98.27
104.41
110.55
116.69
122.83
128.98
135.12
141.26
147.40
153.54
159.69
165.83
171.97
178.11
mm
312
468
624
780
936
1092
1248
1404
1560
1716
1872
2028
2184
2340
2496
2652
2808
2964
3120
3276
3432
3588
3744
3900
4056
4212
4368
4524
Power frequency flashover voltage, kV dry
145
205
270
345
400
455
510
570
640
690
735
785
830
875
920
965
1010
1050
1100
1135
1180
1220
1260
1300
1340
1380
1425
1460 wet
90
130
170
225
275
315
360
405
455
490
525
565
600
635
670
705
740
775
810
845
880
915
950
985
1015
1045
1080
1110
30 184.25
4680 1495
Notes:
■ Flashover voltages are based on the tests according to ANSI C 29.1.
■ Characteristics are given for the strings without screens and arcing horns.
■ Dry power frequency flashover voltage ±5%
■ Wet power frequency flashover voltage ±10%
■ Critical impulse flashover voltage ±8%
1140
2145
2220
2300
2375
2455
2530
2605
1505
1585
1665
1745
1825
1905
1985
2065
765
920
1015
1105
1185
1265
1345
1425
Critical impulse flashover voltage, kV
Positive Negative
220
315
225
320
410
520
615
690
420
530
625
715
815
925
1025
1105
1190
1275
1360
1440
2210
2295
2380
2465
2550
2635
2720
1530
1615
1700
1785
1870
1955
2040
2125
© 2016 Copyright MacLean Power Systems
Technical information subject to change without notice 142