1950s IM Power Relay Timer Help for Solenoid Valves

[marconi]

Your after wiring diagram needs a wire from the relay base 11 to the connector block 4 as shown in my attachment.

If you buy a couple of power (230V ac) initiated interval timers you can replace T1 and T2. If you are not sure send me a link to the ones you intend to buy and I will check they are suitable. Obviously they need to have suitable interval time range. The contacts only carry the small current to operate clamp and inject actuators. Up to you whether to go for 8 pin, 11 pin or din rail ones. Happy to check a photo before you power on should you want me to.

Please keep me informed on progress and DO NOT WORK on live equipment.


note: For power initiated interval timer if applied power goes off then interval output ends at same time.

 

[murd_the_nerd]

Brilliant! I thought the timer power actually supplied the output power. How silly of me. But according to your diagram each Relay in the Timer can have its own power and the Timer simply switches the NC & NO contacts. So you could actually have a set up like this and mix voltages and all sorts:

This has helped me greatly as I completely missed I need to supply power to the contacts! Thanks so much

I will get on to ordering some Interval Timers that function with Power ON and report back how it goes

 

[murd_the_nerd]

And I'm thinking of going for something like this. The 8pins really are more geared to the Power On Interval style and the 11pin options are less common and expensive! The 8pin option below looks like it will do the job just fine One caution might be the 3A vs 6A on current Timers, is that something I should worry about? It is just supplying voltage to a solenoid valve, I can't imagine it drawing a huge amount of power.

Be thankful you don't live the next stop to Antarctica, things are hard to come by down here! The 8pin timer is in stock in Australia so quicker postage. I can get unbranded ones for $10-15 from aliexpress but figure I should get the real deal to be safe and postage can be up to a month.

AT8N
NZD$58

https://nz.element14.com/autonics/at8n-24-240/multi-function-timer-0-05sec-100hr/dp/1736815

Spec sheet:

https://www.farnell.com/datasheets/2010027.pdf

And the much more expensive 11pin option (and I'm sure others too):

TD-78121
NZD$216

TD-78121

Multifunction Timer, 240VAC,

www.galco.com

Great to be at this stage of the process and purchasing new Timers

 

[marconi]

I will check the specifications you sent me today.

 

[marconi]

The relay you have selected is suitable. Order AT8N . (Do not order AT8N1 or AT8N2 ).

One they have arrived we need to set up the timer range and timer mode for I = Interval operation.

You will require two 8 pin bases.

Study the connection diagram carefully for the AT8N so that you place the wires correctly to the 8 pin base.

The current switching capacity of this timer relay is satisfactory for your loads.

Also check by inspection and then with your meter on low ohms range that all items of the machine which are made of metal are indeed connected together and to the earth pin of the plug.

 

[murd_the_nerd]

Legend! I have bought the timers and bases. Will let you know how I get on

 

[marconi]

Greetings from London. I am drinking a New Zealand white wine which jogged my memory about your timers. Any news Sir?

 

[murd_the_nerd]

Nice one and good memory! I have received the new timers and bases. But unfortunately the family household I have my machine stored at came down with Covid so I haven't had a chance to do the wiring and install yet. Hoping to get over there in the next few weeks. Will keep you posted

 

[murd_the_nerd]

Hi Marconi. I finally had a chance to wire in the new timers today I was in a bit of a rush and may have got the + & - the wrong way around. The heater wouldn't start so there is an issue. I either need to force the sequence change on the machine or the wiring is not letting it turn on. There is a relay in series with the two timers (- black wires) that allows the heater to start. I ran out of time to trouble fix.

I would appreciate if you could let me know whether switching the + & - between timer pins 2 and 7 would change anything? It seems just for DC it is wired the other way. Everything else appears fine at first glance...

New wiring:

New vs Old timers:

Timers and relay wiring new vs old:

Wiring diagram from the timer manual:

 

[marconi]

I will study but I regret it will not be right now. I will look as soon as I can later today or this time tomorrow.

M