via Hackaday: A Field Guide to the North American Substation
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One sees a lot of discussion on social media of 12VDC power supplies for ham radio equipment. Some of the recommendations are unsafe.Β Bear in mind that the user could well be a young person with little knowledge and experience and unsafe equipment may put not just themselves at risk of electrocution, but other members of the family / household, people who might try to rescue them.
Firstly, before someone rushes to correct me on the matter of 230V:
The nominal mains input supply voltage in Australia in accordance with AS 60038 is now:
- 230 volts AC Single phase with a tolerance range of + 10% to β 6%
- 400 volts AC Three phase with a tolerance range of + 10% to β 6%
NSW has laws / regulations requiring approval of some electrical articles to protect end users and others. A quote from Explanatory Notes -For the approval and sale of electrical articles in New SouthΒ Wales July 2024:
2.1 Definition of βSellβ
βSellβ includes auction or exchange; offer, agree or attempt to sell; advertise, expose, send, forward or deliver for sale; cause or permit to be sold or offered for sale; hire or cause to be hired; and display for sale or hire. The laws apply to any person who sells an electrical article and includes the manufacturer or importer and any on-seller. The compliance requirements of electrical articles at the time of sale reflects the current applicable product standard as revised or amended. Itβs important that traders effectively manage their
compliance obligations by ensuring that inventory is controlled and that the valid approval status and compliance of this stock is maintained. A personβs obligation under Section 8 of the Act is at the
time the article is sold (for example to a retailer). Once sold it is the obligation of the current holder of the stock for any further sales.
2.2 Declared articles
In order to sell declared articles in New South Wales, the articles must:
1. Be approved as compliant to use prior to sale, evidenced by a NSW Fair Trading Certificate of Approval (or by an accredited Recognised External Approval Scheme.)
2. The approval process must demonstrate that the electrical article meets all relevant Australian Standards and any further requirements that may apply. This process includes the testing of these articles by accredited laboratories.
3. Be marked with the NSW approval mark or an approved alternate mark (see 3.3.)
4. Definitions of declared articles and their associated safety standard/s are attached
Battery chargers and Extra Low Voltage supplies are declared articles.
States each make these regulations, this is NSW but similar regulations apply in other states.
Note that you do not have to be a commercial seller to be in scope of these regulations, read the definition of βsellβ carefully.
Some equipment recommended by online experts is actually a power supply component intended to be incorporated into some larger piece of equipment, and enclosed in a way that prevents accidental contact with live conductors / terminals / parts, and they would never obtain the approval necessary to be sold as an ELV power supply article.
Online market places offer a wide range of battery chargers and ELV power supplies, many of which may not have the required approvals. Similarly Chinese online market places are likely to offer equipment that does not have the required approval.
There are retail sellers of approved ELV power supplies suited to ham radio equipment.
I purchased on of these batteries on Big-W online for a mid-high price ($77), expensive enough compared to genuine to expect it would have near to rated capacity.
Above is a pic of the battery advertised. The delivered battery was labelled 7Ah.
They say a picture is worth a thousand words:
So, there it is, after three charge discharge cycles to develop full capacity, two measured discharge cycles. It measures <2Ah, <30% of rated capacity.
Full refund claimed, promptly processed by Big-W Online β return label within a few hours.