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Porcelain Indoor Standoff Insulators

Indoor Standoff Insulators,Precision Support for Switchgear

Porcelain bodies with brass fittings on each end and center mounting holes — the reliable support for copper and aluminum bus bar lines inside electrical equipment.

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2.5 – 15kVVoltage Range

Brass FittingsBoth Ends

70100–70200Series Types

US & EUMain Markets

⚡ 2.5kV – 15kV Porcelain Indoor Standoff Insulators

Product Overview

Built for Indoor Bus Bar Support

Our porcelain indoor standoff insulators combine a porcelain body with brass fittings on each end and a center mounting hole in each fitting — used to support copper or aluminum bus bar lines in various electrical equipment. Supplied from 2.5kV to 15kV across the 70100 to 70200 series: 70100, 70105, 70110, 40115, 70125, 70130, 70135, 70140, 70145, 70150, 70151, 70152, 70155, 70160, 70165, 70169, 70170, 70174, 70175, 70176, 70185, 70190, 70195, 70200, 70205, 70210, 70214, 70215.

Voltage Range

2.5kV – 15kV

Series

70100 / 70105 / 70125 / 70150 / 70155 / 70160 / 70200

Fittings

Brass, center mounting hole

Markets

Americas, Europe, East Asia

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✓IEC Compliant✓Brass Fittings✓Center Mounting Hole✓Anti-Pollution Glaze

0kV

Max Rating

0kV

Min Rating

Standard Series

Quality Tested

Full Ratings & Specifications

Complete Specification & Cross-Reference Table — 28 Catalog Numbers

Dimensions, clearances, electrical ratings and strength ratings for every catalog number, 2.5 kV to 15 kV. Column 1 is the ROYAL catalog number; column 2 lists the legacy USA catalog numbers — match your existing part number there to find the ROYAL equivalent, then confirm the insert thread. Use the voltage filter to narrow the list; on mobile, scroll the table sideways.

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Indoor standoff insulator ratings — 28 catalog numbers, 2.5 to 15 kV
ROYAL No.	USA No.	Dimensions (in.)		Style No.	Insert thread (each end)	Clearance (in.)		Electrical rating		Strength rating (lbs)			PCS / Carton
ROYAL No.	USA No.	Dia.	Height	Style No.	Insert thread (each end)	Min. creep	Strike	Rating (kV)	BIL (kV)	Cantilever 5/8 in. above top	Tension	Compression	PCS / Carton
2047	70100	2	2-1/2	1	3/8″-16 UNC	3	2-1/2	2.5	45	550	1,375	6,500	25
2053	70105	2	3-1/2	1	3/8″-16 UNC	4-1/2	3-1/2	5	75	350	1,400	6,500	25
2056	70110	2	5-1/8	1	3/8″-16 UNC	7	5-1/8	8.7	95	225	1,600	6,500	25
2057	40115	2-1/2	2-9/16	1	3/8″-16 UNC	3-1/2	2-9/16	2.5	60	525	1,900	8,000	25
2058	70125	2-1/2	3	1	3/8″-16 UNC	4-1/2	3	5	60	425	1,775	8,000	25
2054	70130	2-1/2	4	1	3/8″-16 UNC	7	4	8.7	75	425	1,775	8,000	25
2059	70135	2-1/2	5	1	3/8″-16 UNC	7-1/2	5	8.7	95	300	1,700	8,000	25
2044	70140	2-1/2	6	1	3/8″-16 UNC	10-1/2	6	15	110	225	1,850	8,000	25
2060	70145	2-3/4	3-1/8	1	3/8″-16 UNC	5	3-1/8	5	60	500	1,900	8,500	25
2041	70150	3-1/8	2-5/8	1	1/2″-13 UNC	4	2-5/8	5	60	525	1,800	10,000	25
2061	70151	3-1/8	2-5/8	1	3/8″-16 UNC	4	2-5/8	5	60	525	1,800	10,000	25
2062	70152	3-1/8	2-5/8	1	1/2″-13 or 3/8″-16 UNC	4	2-5/8	5	60	525	1,800	10,000	25
2048	70155	3-1/8	3-3/8	1	3/8″-16 UNC	5	3-3/8	5	60	515	1,925	10,000	25
2063	70160	3-1/8	3-3/8	1	1/2″-13 UNC	5	3-3/8	5	60	515	1,925	10,000	25
2064	70165	3-1/8	4	1	1/2″-13 UNC	6	4	7.5	75	510	2,000	10,000	25
2049	70169	3-1/8	5	1	3/8″-16 UNC	7-1/4	5	8.7	95	275	1,725	10,000	25
2050	70170	3-1/8	5	1	1/2″-13 UNC	7-1/4	5	8.7	95	275	1,725	10,000	25
2051	70174	3-1/8	6	1	3/8″-16 UNC	10-5/8	6	15	110	260	1,600	8,000	25
2052B	70175	3-1/8	6	1	3/8″-16 or 1/2″-13 UNC	10-5/8	6	15	110	260	1,600	8,700	25
2052	70176	3-1/8	6	1	1/2″-13 UNC	10-5/8	6	15	110	260	1,600	8,000	25
2065	70185	3-1/2	3	1	1/2″-13 UNC	5	3	5	60	—	—	—	25
2055	70190	3-1/2	3-1/2	1	1/2″-13 UNC	6-1/4	3-1/2	7.5	75	700	2,400	12,000	25
2066	70195	3-1/2	4-1/2	1	1/2″-13 UNC	6-1/4	4-1/2	8.7	95	400	1,725	12,000	25
2045	70200	3-1/2	3-1/4	2	1/2″-13 UNC	4	3-1/4	5	60	800	2,750	15,000	25
2042	70205	4	3-15/16	2	1/2″-13 UNC	7-5/8	3-15/16	8.7	75	750	2,350	20,000	18
2046	70210	4	4-5/8	2	1/2″-13 UNC	9-1/4	4-5/8	8.7	95	575	1,900	20,000	25
2043B	70214	4	6	2	3/8″-16 UNC	12-3/8	6	15	110	375	2,000	20,000	120
2043	70215	4	6	2	1/2″-13 UNC	12-3/8	6	15	110	375	2,000	20,000	120
Cantilever rating measured 5/8 in. above the top of the insulator. All dimensions and ratings in inches and pounds (imperial). Metric data available on request. Gray glaze standard; other glaze colours on request. Catalog numbers 70152 and 70175 available with either insert thread.

Can’t find your number? Send us a photo of the marking on your old insulator and we’ll match it — Contact us.

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Download datasheet (PDF)

Why This Product

Key Technical Advantages

Brass Fittings

Corrosion-resistant brass fittings with center mounting holes.

Bus Bar Support

Purpose-built to support copper and aluminum bus bar lines.

Proven in US Market

Primary market is America, with exports to Europe and East Asia.

Competitive Quality

High quality with very competitive pricing for volume orders.

Optimized Design Features

✓Porcelain body with brass fittings both ends
✓Center mounting hole in each fitting
✓Full range 2.5kV to 15kV
✓70100 – 70200 standard series
✓Gray glaze resists dirt and pollutants

Industry Applications

✓Indoor switchgear bus bar support
✓Copper & aluminum bus bar lines
✓Electrical equipment insulation
✓Substation control rooms
✓Low & medium voltage panels

Good to Know

Frequently Asked Questions

What standards are ROYAL standoff insulators manufactured to?

ROYAL indoor standoffs follow the ANSI dimensional series from 2.5 kV to 15 kV. Every shipment includes inspection and routine test records; additional quality documentation is available on request.

Can I replace insulators from another brand without re-drilling my switchgear?

Yes — the series is dimensionally interchangeable. Match your number against the USA No. column of the specification table above, confirm the insert thread (3/8″-16 or 1/2″-13 UNC), and the replacement drops straight onto existing mounting holes.

What is your minimum order quantity (MOQ)?

Our minimum order quantity is 500 pcs. Mixed catalog numbers can be combined in a single container — send us your item list and we will structure the order to suit.

How long is the typical lead time?

Standard production lead time is 45 days from order confirmation. Send us your item list and we will confirm a delivery schedule for your exact quantities.

Do you offer OEM branding, custom colours or special threads?

Yes. Gray glaze is standard and other glaze colours are available on request. Custom markings and export packing can be arranged — catalog numbers 70152 and 70175 are offered with either 1/2″-13 or 3/8″-16 insert thread.

How are the insulators packed for export?

Cartons, with the pieces-per-carton count shown in the ratings table. Export pallets, custom carton marking and container loading plans are available on request.

Can I get samples before placing a container order?

Yes — samples are available for evaluation. Send us the model number, quantity and destination port and we will quote the sample cost and freight.

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Send us your specifications — voltage class, BIL, drawings or standards — our engineering team will respond within one business day with pricing and technical recommendations.

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Free technical consultation & sample support
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