The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Topic Options
Rate This Topic
#163902 - 05/20/07 02:52 PM (AU) HPM 889 Power Outlet
Webmaster Offline


Registered: 10/07/00
Posts: 3142
Loc: NY, USA

The two photos are of an Australian made HPM 889 series outlet with extra switch.

These were produced in the mid to late 1960s and I managed to purchase nine of these outlets still in bags from Ebay recently.

The outlet is designed to only allow the switch for the power outlet to be turned ON when a plug is inserted into the outlet.

Darren Carroll
Alice Springs, NT, Australia

Super Rod Cable Installation Tools

Super Rod Cable Rod System
Super Rod Cable Rod System -
Best Product of the Last 50 Years by members of NICEIC

#164026 - 05/23/07 09:19 AM Re: (AU) HPM 889 Power Outlet [Re: Webmaster]
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I'm sure I've seen some old British BS546 15-amp (round-pin) outlets which had a similar feature of locking the switch in that way, but I might be imagining things.

What was the second switch used for in a typical application? Lighting?

#164062 - 05/24/07 04:43 AM Re: (AU) HPM 889 Power Outlet [Re: pauluk]
32VAC Offline

Registered: 06/28/04
Posts: 203
Loc: Alice Springs, NT, Australia
The switch on the left of the faceplate is a 10 amp switch that can be used for lighting, fans, heaters or any application where a switch was needed.

These outlets were common in bedrooms where only one power outlet was needed, saved running extra wire down the wall. You used a mixed (light/power) circuit and took the active from the terminal on the back to the switch & then run the switch wire (controlled by the switch on the left) back to the light.

#164149 - 05/26/07 05:35 AM Re: (AU) HPM 889 Power Outlet [Re: 32VAC]
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
I seem to recall seeing a more modern version of this idea in a Jaycar catalog some years back: Dual general-purpose outlet each with its own switch, plus a third switch centrally mounted. It had the little round rocker switches -- Like some of the Clipsal range here.

Similar to this type but with third switch top center:

Edited by pauluk (05/26/07 05:44 AM)
Edit Reason: Added image

#164169 - 05/26/07 01:20 PM Re: (AU) HPM 889 Power Outlet [Re: pauluk]
Trumpy Offline


Registered: 07/05/02
Posts: 8532
Loc: SI,New Zealand
It's interesting that sockets had safety shutters in them back then.
It's my guess that the shutters operated the interlock on the switch.

Here's an HPM horizontal double socket outlet with extra switch:

Popular here in kitchens where the switch is often used to power a socket outlet supplying either a dishwasher or waste disposal unit.
They are also used in bathrooms for shaver sockets and the switch used for vanity unit lighting.

Edited by Trumpy (05/26/07 01:28 PM)
Edit Reason: To add image
Let's face it, these days if you're not young, you're old - Red Green grin


ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals