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ASTM D120 Insulating Gloves

June 12th, 2018

ASTM D120 Insulating Gloves

uploaded by Chris Dodds - Thorne & Derrick

ASTM D120 specification covers manufacturing and testing of rubber insulating gloves for protection of workers from electrical shock.

Two types of insulating gloves are provided and are designated as Type I, non-resistant to ozone, and Type II, resistant to ozone.

Six classes of ASTM D120 compliant insulating gloves differing in electrical characteristics are provided and are designated as Class 00, Class 0, Class 1, Class 2, Class 3 and Class 4.

The following tests shall be performed as part of the ASTM D120 Standard Specification for Rubber Insulating Gloves:

ac proof test
ac breakdown test
ac moisture absorption/proof test
dc proof test
dc breakdown test
ozone resistance test
chemical tests
tensile strength
tear resistance test
puncture resistance test

This following abstract is a brief summary of the referenced ASTM D120 standard – this is provided for informational purposes only and not an official part of the ASTM D120 standard; the full text of the standard itself must be referred to for its use and application.

ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

Scope Of ASTM D120

1.1 This specification covers manufacturing and testing of rubber insulating gloves for protection of workers from electrical shock

1.2 Two types of gloves are provided and are designated as Type I, non-resistant to ozone, and Type II, resistant to ozone

1.3 6 classes of insulating gloves each differing in electrical characteristics are provided and are designated as Class 00, Class 0, Class 1, Class 2, Class 3, and Class 4

1.4 The values stated in SI units are to be regarded as standard. See IEEE/ASTM SI 10

1.5 The following safety hazards caveat pertains only to the test method portion, Sections 16, 17, 18, and 19, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Insulating Gloves

The following table enables the selection of ASTM D120 Insulating Gloves according to working voltage and insulating class category – should you require any assistance with the correct type, specification or size of gloves please do not hesitate to contact us.

CATU Electrical Code	Insulating Glove Class	Voltage	Type	Inches	Colour
CATU CGA-00	Class 00	≤ 500V	1	14	Black
CATU CGA-0	Class 0	≤ 1000V	1	14	Black
CATU CGA-1	Class 1	≤ 7500V	1	14	Bi-Colour
CATU CGA-2	Class 2	≤ 17000V	1	14	Bi-Colour
CATU CGA-3	Class 3	≤ 26500V	1	14	Bi-Colour
CATU CGA-4	Class 4	≤ 36000V	1	16	Bi-Colour

Distributors & Stockists For CATU Electrical

Insulating Matting | Voltage Detectors | Insulating Gloves | Substation Safety | Arc Flash Clothing Protection

How To Purge Air Bubbles From Cembre Hydraulic Crimping Tool – Model HT51

June 12th, 2018

Cembre HT51 Hydraulic Crimping Tool

Uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager

Cembre HT51

Thorne & Derrick International are Main UK Stockists and Suppliers of Cembre tools including crimping and cutting types for all constructions of LV MV HV cable including medium/high voltage 11kV/33kV power cables.

The following short article provides useful instructions about how pure air bubbles correctly from the Cembre hydraulic circuit in relation to model HT51 cutting tool – built in safety valve also by-pass the oil supply when maximum pressure has been reached.

The following excerpts are taken from the Operating Manual of Cembre HT51 hydraulic crimping tool – however this information applies to the following tool model variants Cembre HT51-KV (insulated version).

Cembre HT51 crimping tool is lightweight and ideal for use in working confined switchgear and other LV-HV cable jointing, splicing and terminating applications.

The hydraulic crimping tool features spring loaded handles allowing the Cembre die sets to be advanced with one hand – the other hand is free to position the electrical connector or cable lugs prior to crimping.

For competitive prices, stock availability and technical advice about the Cembre HT51 tool please do not hesitate to contact us.

Purging Air Bubbles From Cembre HT51 Crimping Tools

HT51 Crimping Tool Position For Maintenance Operations

Air in the hydraulic circuit may affect the performance of the crimping tool. For example no lower die advancement, slow advancement of the lower die and lower die pulsating would all cause issues.

If this is the case proceed as follows:

4.1) To Purge Air Bubbles From Hydraulic Circuit

a – Hold tool upright in a vice with handles open (Fig 3).

b – Unscrew the main handle (04) from the body (13) to expose the rubber oil reservoir (03).

c – Remove reservoir cap (02).

d – Operate moveable handle (36) several times, in order to advance the tool ram (16).

e – Press the pressure release lever (44) to retract the ram (16), discharge oil pressure from the circuit and return all oil to the reservoir.

f – Repeat points (d – e) five times, to ensure all air bubbles in the hydraulic circuit are purged into the reservoir.

g – Remove all air from reservoir.

If the oil level is low top up as directed below.

h – Fit reservoir cap (02).

i – Assemble main handle (04) to tool body.

If the tool continues to malfunction return the tool for service.

Oil Top Up

Every six months check the oil level in the reservoir. If necessary, top up the oil level to the upper lip of the reservoir and remove all air from the reservoir (as described above).

Always use clean recommended oil – AGIP ARNICA 32 or SHELL TELLUSTX 32 or equivalent for HT51 and AGIP ITE360 or ESSOTRANSFORMER P60 or equivalent for HT51-KV

♦ Warning: Do not use old or recycled oil

♦ Warning: Do not use hydraulic brake fluid

HT51-KV tool contains oil with a high insulating power so it is imperative that you don not pollute it with other types of oil!

Cembre HT51 supplied with protective carrying case, tool manual and crimp die sets

Cutting & Crimping Tools

Cable Crimping & Cutting Tools

This post is from a series of articles written to provide advice and guidance on the care and servicing of Cembre cable cutting and crimping tools.

Thorne & Derrick

Cembre Cutting Tools Instructions For Use – Model B-TC950

June 12th, 2018

Cembre B-TC950 Cutting Tool

Uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager

Cembre B-TC950

The following short article provides useful instructions about how to correctly use the Cembre model B-TC950 cutting tool – prolonged use of the cordless hydraulic cutting tool can cause bluntening of the blades when cutting conductors, wires and cables.

The following excerpts from the Operating Manual of Cembre B-TC950 – however this information applies to the following tool model variants B-TC950A B-TC950E B-TC950T.

Cembre B-TC50 is a battery operated cable cutting tool suitable for diameters up to 95mm outside diameter and features their new Li-Ion 18V 4 Ah batteries providing improved cutting speed and cutting force with double-speed action for jointing and terminating copper or aluminium type cables.

For competitive prices, stock availability and technical advice about the Cembre B-TC950 tool please do not hesitate to contact us.

Instructions For Use – Model B-TC950

CEMBRE B-TC950

Cembre B-TC950 Battery Operated Hydraulic Cable Cutting Tool - Spare Parts

Locking lever
Upper cable cutting blade
Lower cable cutting blade
Handle grip
Operating button
Pressure release button
Battery
Battery capacity indicator
Battery check button
Battery release
LED worklight
Ring for shoulder strap

♦ Warning: Before starting any work, check the battery charge and recharge if necessary.

Follow the instructions in the battery charger user manual.

The tool can be easily carried using either the handle or the shoulder strap attached to rings (12).

To replace the battery, remove it by pressing the release button (10) then insert the new battery, sliding it into the guides until it locks.

Cutter Head Rotation

For ease of operation the tool head can rotate through 335° allowing the operator to work in the most comfortable position.

♦ Warning: Do not attempt to rotate the cutting head when the hydraulic circuit is pressurised.

Setting

Figure 3 & 3a Insert the conductor between the blades up to the cutting point

Insert the conductor between the blades, up to the desired cutting point (Fig. 3). For a running conductor, press the locking lever (1) and open the tool head (Fig 3a).

Fully retract the lower blade (3) before attempting to open the tool head. With the conductor on the lower blade (3), close the tool head and fully secure the lever (1).

♦ Warning: Before commencing the cutting operation ensure that the lever (1) is fully secured: partial closure may damage the tool head.

Cutting Blade Advancement

Press the operating button (5) (Ref. to Fig. 3) to activate the motor-pump. The ram will gradually move forward until the lower blade (3) touches the conductor.

To halt the advancement release the button (5) and the motor will cut out.

♦ Warning: Make sure the blade is exactly positioned on the desired cutting point otherwise re-open the blade following instructions and reposition it.

Cable Cutting

Firmly hold the tool and operate the button (5) to gradually move the lower blade (4) to cut through the conductor.

When the cut is performed release the button (5) to ensure the maximum pressure relief valve isn’t activated.

LED Worklights

Whilst the tool is in operation, the work area is illuminated by two high luminosity LED Worklights that switch off automatically at the end of the cycle.

Blade Retraction

By operating the pressure release button (6) the ram will retract and open the lower blade.

Battery Status

Figure 4 Battery Level Indicator

The battery is equipped with LED indicators that indicate the remaining battery life at any time by pressing the adjacent button (9):

4 LEDs illuminated: fully charged
2 LEDs illuminated: 50 % capacity
1 LED flashing: minimum charge, replace the battery

Worklights (11) illuminated combined with an alarm audible when the operating button (5) is pressed (Fig.4) is an indication that the battery voltage has dropped below a minimum safety threshold

Under these conditions the tool will not start and the battery should be replaced or recharged (80 minutes to fully recharge battery).

After each working cycle and the extraction of the battery from the tool, an integrated battery cut-off device will operate after approximately 70 s.

The LED nearest to button (9) will then flash 5 times each 14 s approx. The battery will be reactivated when it is reintroduced into the tool and the operating button is pressed.

Using The Battery Charger

Carefully follow the instructions in the battery charger user manual.

Cutting & Crimping Tools

Thorne & Derrick

Cold Shrink Joints | Jointing LV Cables Using 3M Cold Shrink Cable Joints

June 11th, 2018

➡ Contact Thorne & Derrick International for the most competitive prices and largest UK stocks of Cold Shrink Cable Joints manufactured by 3M Electrical – specified extensively in the hazardous area industries including onshore and offshore oil, gas and petrochem for safe cable joints in potentially explosive atmospheres where “hot-working” is not permitted.

♦ See also the 3M Electrical range of Offshore Cable Joints suitable for power, control and instrumentation cables in the marine and offshore industries – includes NEK606 (RFOU BFOU EPR) and BS6883/BS7917 (UKOOA) offshore cables and specifications of cable joints compliant with the recommendations of the ATEX Directive for hazardous area cable installations distributing LV MV HV electricity supply.

Cold Shrink Joints – LV HMV HV Power Cable Joints 600V/1000V 11kV 33kV

How To Apply 3M Cold Shrink Tubing – Underground Cable Joints

June 11th, 2018

A series of How-To videos for repairing, jointing and terminating cables using 3M Cold Shrink & Scotchcast products.

Cold Shrink

This video by 3M Electrical shows how to apply 3M Cold Shrink tubing safely for underground cable jointing processes and applications.

3M Cold Shrink tubing is a series of open-ended, tubular rubber sleeves, which are factory expanded and assembled onto a removable core – Cold Shrink tubes are supplied for field installation in a pre-stretched condition.

The 3M Electrical video shows how to install the cold shrink tubing and the full underground cable jointing process which is explained below:

Position 3M Cold Shrink outer tube splice body and copper sleeve over the cable
Install connector – a number of the 3M kits come complete with connectors
Many connectors can be used providing they suit the requirements of the cable and fit within the Faraday cage
Using 3M Cable Cleaning Wipes clean the cable and connector
Once cleaned apply 3M P55 silicone grease leaving the connector until last to avoid contamination and smoothing out the grease to give an even coverage
Move the splice body into place over the connector before unwinding the removable core to install the tube allowing the tube to shrink and form a waterproof seal
Apply a layer of 3M Scotch Seal 5313 Tape to the end of the joint – a comfortable and durable mastic with excellent moisture and environmental seal
Now tape over with the 3M Scotch 2228 Mastic Tape – a conformable self amalgamating temperature stable mastic
Then reposition the copper sleeve over the joint fixing in place with 3M Constant Force Springs
Now tape over with 3M Scotch 13 Semi Conducting Tape before applying more 3M Scotch 2228 Mastic Tape over the top
Move the first 3M Cold Shrink Tube into place ensuring one end of the joint is completely covered
Apply 3M Scotch 2228 Mastic Tape in preparation for the last protection tube
Finally install the second 3M Cold Shrink Outer Protection Tube making sure to overlap the previous protection tube

Cold Shrink – invented by 3M over 40 years ago and now the preferred technology for heat-free jointing, terminating, sealing and abandonment of LV HV cables

We hope you find this video informative and educational, contact T&D for technical support, quotations and stock availability for 3M Cold Shrink Tubing.

➡ Visit 3M Electrical for further information about joints, terminations, tapes and insulation to seal, repair, splice and connect LV MV HV cables.

3M Electrical Products Stocked By Thorne & Derrick International

Blog

ASTM D120 Insulating Gloves

Scope Of ASTM D120

Insulating Gloves

How To Purge Air Bubbles From Cembre Hydraulic Crimping Tool – Model HT51

Cembre HT51

Purging Air Bubbles From Cembre HT51 Crimping Tools

Cable Crimping & Cutting Tools

Thorne & Derrick

Cembre Cutting Tools Instructions For Use – Model B-TC950

Cembre B-TC950

Instructions For Use – Model B-TC950

CEMBRE B-TC950

Thorne & Derrick

Cold Shrink Joints | Jointing LV Cables Using 3M Cold Shrink Cable Joints

How To Apply 3M Cold Shrink Tubing – Underground Cable Joints

Cold Shrink

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