TOMZN 2P DC Circuit Breaker 20A- 12V-1000V Wide RangeDC MCB for PV System (TOMZN TOB7Z-63)

The TOMZN TOB7Z-63 is a 2P DC mini circuit breaker, listed as a 20A unit for solar photovoltaic systems working at up to 1000V DC. It suits homeowners, installers and commercial solar owners in Bangladesh who need overload and short-circuit protection on the DC side of a PV array.

• Overview
• Key features
• Specifications
• How to use and set up
• Compatibility and what is in the box
• Who should buy it in Bangladesh
• Alternatives in our store
• Warranty and support
• Delivery, returns and ordering
• Frequently asked questions

About the TOMZN TOB7Z-63 DC circuit breaker

The TOMZN TOB7Z-63 is a 2P DC circuit breaker from the TOB7Z-63 series, made for the direct current side of solar installations. According to the listing, it protects against overloads and short circuits, which helps guard solar panels, inverters and the wiring between them. For a solar owner in Bangladesh, that is the core job: stopping a fault from spreading into expensive equipment.

The listing describes the TOMZN TOB7Z-63 as suitable for DC applications up to 1000V, and it is offered in 10A, 20A and 32A ratings. This product page covers the 20A version named in the title. If your string current is different, check the rating with your installer before you order, because a breaker is only as useful as its match to the array.

Bangladesh’s grid and climate make protection worth planning for. Load-shedding, power fluctuations and the humid weather common in Dhaka and other cities all put strain on electrical systems, so a clear protection point in the DC section is sensible. A TOMZN TOB7Z-63 in the combiner box does not replace good design, but it gives a defined place where a fault can be isolated.

Key features

1000V DC rating for modern solar arrays

The listing gives the TOMZN TOB7Z-63 a 1000V DC rating and describes it as designed for the high DC voltages common in modern solar PV arrays. The title also gives a wide range of 12V to 1000V. In a string of panels wired in series, the voltage across the string can be much higher than the voltage of a single panel, so the voltage figure deserves a careful look in your design. Ask your installer to compare the string voltage in your plan with the rating on this breaker before you buy. Using a breaker rated for the array is the first step in a sound DC layout.

Dual pole (2P) protection

According to the listing, the 2P design disconnects both positive and negative DC lines together when a fault occurs. The maker lists this as a way to enhance system safety. In practice, the incoming positive and negative cables from the array each connect to one pole, so both conductors are handled by the same device. When you plan a DC run, show both lines passing through the TOMZN TOB7Z-63 on your wiring sketch, and make sure your installer does the same. Both poles sit in one unit, which is the point of the 2P design the listing describes.

Current ratings from 10A to 63A

The listing says the TOB7Z-63 series comes in ratings including 10A, 20A and 32A, and that the series also supports up to 63A for larger configurations. This page covers the 20A model named in the title, and our range includes another listing from the same family for other ratings. Matching the current rating to your PV string is the reason for choosing a particular size, so compare your string current with the options before you order. Your installer can confirm the right size from your design, and the TOMZN TOB7Z-63 should only be chosen once that check is done.

Overload and short-circuit protection

The listing describes a thermal-magnetic tripping mechanism that protects against sustained overcurrents, which it says helps prevent overheating and potential damage. It also describes a rapid magnetic trip unit that disconnects the circuit in a short circuit, which the maker says minimises arc flash risks and equipment damage. The TOMZN TOB7Z-63 is designed for manual operation and trips to the OFF position in either case, as the listing explains. A trip is a signal to look for the cause before switching the circuit back on, which is general good practice for any PV installation.

High breaking capacity (6kA)

The TOMZN TOB7Z-63 listing gives a breaking capacity of 6kA and describes it as the ability to interrupt high fault currents up to 6000 amps. The maker presents this as protection under severe fault conditions. The figure is one of the items to talk through with your installer when you plan the protection for your system. Breaking capacity is one entry in a longer checklist, so do not rely on it alone when deciding on a breaker.

DIN rail mounting and ON/OFF indication

The listing says the TOMZN TOB7Z-63 mounts on a standard 35mm DIN rail, which the maker describes as compatible with most electrical distribution boards and enclosures. It also has a clear ON/OFF indication, which the listing describes as useful for status monitoring and troubleshooting. The breaker is designed for manual operation, so you switch it by hand, and it trips to OFF on overload or short circuit. This makes it easy to see the state of the circuit during a site visit.

Specifications

The specifications below for the TOMZN TOB7Z-63 are the values listed on the product listing, and we have not added figures beyond them.

These are listed specifications from the product listing; please check them against your own system design.

How to use and set up

The listing gives installation guidance for the TOMZN TOB7Z-63, and the points below summarise it in general terms. Always follow the maker’s instructions, and have a qualified electrician or solar technician carry out the work.

Safety first: before any electrical work, disconnect all power sources to the solar system, including both the AC and DC sides. Use suitable personal protective equipment. Only start work once the system is fully isolated.

Mounting: fix the TOMZN TOB7Z-63 securely onto a 35mm DIN rail inside a suitable enclosure, such as a DC combiner box or distribution board, that gives adequate protection against environmental conditions. Bangladesh’s humid months make the enclosure choice worth discussing with your installer early in the plan.

Wiring: connect the incoming DC positive and negative cables from the solar array, or combiner box, to the top terminals of the 2P breaker. Connect the outgoing DC positive and negative cables, going to the inverter or charge controller, to the bottom terminals. When wiring the TOMZN TOB7Z-63, the listing asks for correct polarity and tight connections, typically 2.5 Nm of torque. Tighten to that specification rather than by feel.

Cable sizing: use DC-rated cables of an appropriate gauge for your current and voltage, so that the run does not overheat or lose too much voltage. Your installer will size the cables from the design.

Testing: the listing suggests carrying out continuity and insulation resistance tests after installation and before re-energising the system. Keep a written record of the results so your installer can compare them later.

Operation: the TOMZN TOB7Z-63 is designed for manual operation. The ON position closes the circuit so power flows, and the OFF position opens it. In an overload or short circuit, the breaker trips automatically to OFF, as the listing explains. Before first use, read the maker’s instructions and your installer’s plan together so that the two match.

Compatibility and what is in the box

The confirmed item on this page is the TOMZN TOB7Z-63 2P DC circuit breaker, the 20A version named in the title. The listing confirms its 1000V DC rating, its 2P design, 35mm DIN rail mounting and its use in DC combiner boxes, residential rooftop systems, commercial and industrial projects, off-grid and on-grid systems, and solar street lights and water pumping systems.

The listing does not confirm which inverter, charge controller or solar panel brands the breaker is matched with, so that check belongs with your installer and the specifications of your own equipment. Keep the DC voltage and current of your array in view when you compare the options.

What is in the box: the listing does not confirm the package contents, so ask us before ordering if you need that detail. We will not guess here.

Compatibility with a DC system depends on the array voltage, the current and the enclosure, so bring those details to your installer before you buy the TOMZN TOB7Z-63. Share the model code with them as well.

Off-grid and battery systems: the listing names off-grid systems among its applications, which is useful for battery-based homes in areas that face load-shedding. Ask your installer whether the 20A rating suits the battery bank and charge controller in your design.

Who should buy it in Bangladesh

The TOMZN TOB7Z-63 suits a few realistic buyers. Each scenario below is a starting point to test against your own plan, not a promise of how the product will perform in your system.

Rooftop homeowners in Dhaka and other cities: if you are adding a DC string or replacing an old breaker on a home solar array, the TOMZN TOB7Z-63 gives you a 2P DC device with a 1000V rating and a 20A option. Your installer should confirm the string current and voltage first, then decide whether this model fits.

Installers and electricians building DC combiner boxes: the listing describes the breaker as a primary protective device for individual PV strings within a combiner box. For this use, the TOMZN TOB7Z-63 suits the DIN rail layout that most distribution boards use, and you can plan the two poles for each string on one drawing.

Small commercial and office solar owners: factories, offices and warehouses can use the listing’s idea of scalable protection for larger PV arrays. The listing names commercial and industrial projects as an application, so compare the rating options and talk to your installer about the layout across several strings before you commit.

Off-grid and battery owners in load-shedding areas: a home running on batteries needs reliable protection on the DC side, and the listing names off-grid systems as a suitable application. If your battery bank and charge controller sit on a DC circuit, the TOMZN TOB7Z-63 may be a candidate, and your installer can check it against the design.

Street light and pumping projects: the listing names solar street lights and water pumping systems as applications for standalone DC circuits. Contractors and community projects in Bangladesh can use the TOMZN TOB7Z-63 for that job, and the installer’s drawing should show the breaker rating clearly.

Buyers who are not sure: if you are unsure whether you need a 10A, 20A or 32A rating, or whether the 2P design suits your array, do not guess. Send us your plan through the contact details in the delivery section, and let your installer settle the choice against the maker’s instructions.

Who should skip it: if your system is not DC-based, a DC breaker is the wrong tool. This product is aimed at DC circuits only, so check the wiring before you order.

Alternatives in our store

If the TOMZN TOB7Z-63 does not match your plan, you may find a better fit elsewhere in our range. The listing for the same TOB7Z-63 family is available as TOMZN TOB7Z-63 2P DC Circuit Breaker – 10A, 20A, 32A Solar PV MCB, 12V–1000V Wide Range DC MCB for PV System, which is worth comparing if you need a different rating.

For a smart wall switch, see SONOFF WiFi Smart Wall Touch Switch T3 UK 3 Gang- Compatible With Alexa, Google Assistant – Black Color, which is a smart wall switch in our range. For a plug-in option, the LDNIO Z4 Universal Plug 6A Max (ABS V0) is a universal plug in our range. For several sockets, the Deli CT705ES 3 Pin 6 Port 3 Meter Power Strip With Surge Protection is a power strip in our range.

You can browse the whole category at Smart Switches & Electrical. For general background on the smart plug category, read the Wikipedia article on smart plugs.

Warranty and support

Warranty: 7 Days seller warranty.

Delivery, returns and ordering

We deliver all over Bangladesh and you pay cash on delivery. Delivery usually takes 1–3 days inside Dhaka city and 2–5 days outside Dhaka.

You can return it within 7 days of delivery (see our Delivery & Returns policy). If you are ordering the TOMZN TOB7Z-63 for a project, plan the timing with your installer so that the breaker arrives before the wiring work starts.

Questions before ordering: call 09638054751, message us on Facebook Messenger or email care@gadgetsuperb.com. Before you write, note the TOMZN TOB7Z-63 model code, your current rating and your array voltage. Full policy details are on our policy page.

Frequently asked questions

What is the TOMZN TOB7Z-63 used for?

It is a 2P DC circuit breaker that the listing presents for protecting solar PV systems against overloads and short circuits. It is aimed at solar panels, inverters and the DC wiring between them.

Is the TOMZN TOB7Z-63 rated for 1000V DC?

Yes, the listing gives a 1000V DC rating and describes a wide range of 12V to 1000V. Check that the rating covers the voltage of your own array with your installer.

Which current ratings does the TOMZN TOB7Z-63 come in?

The listing says the series comes in 10A, 20A and 32A and supports up to 63A. This product page covers the 20A version named in the title.

Does the TOMZN TOB7Z-63 disconnect both DC lines?

Yes, according to the listing, the 2P design disconnects both positive and negative DC lines when a fault occurs. The maker lists this as a way to enhance system safety.

How is the TOMZN TOB7Z-63 mounted?

It mounts on a standard 35mm DIN rail inside a suitable enclosure, such as a DC combiner box or distribution board. Your installer will plan its position within the enclosure.

What warranty comes with the TOMZN TOB7Z-63?

The listed warranty is 7 Days seller warranty. Ask us about any support questions before ordering.

Can I return the TOMZN TOB7Z-63 if it does not suit my system?

Yes, you can return it within 7 days of delivery under our Delivery & Returns policy. Check the policy page for the full steps.

How long does delivery of the TOMZN TOB7Z-63 take?

Delivery usually takes 1–3 days inside Dhaka city and 2–5 days outside Dhaka. We deliver all over Bangladesh and you pay cash on delivery.

Does the listing say the TOMZN TOB7Z-63 meets IEC/EN 60947-2?

Yes, the listing says it meets IEC/EN 60947-2. We cannot add further documents from the listing, so ask us before ordering if you need more detail.

Who should install the TOMZN TOB7Z-63?

The listing says installation should be done by a qualified electrician or solar technician who knows DC electrical systems. Follow the maker’s instructions throughout.