Electrical SECTEC 35II Fault Light

Brad Hardwick

New Member
Oct 19, 2017
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Vic
Hi,
Recently the battery light has stopped turning on my SETEC 35II and when mains power is cut it is not supplying power to the van via the battery. All 12V light etc work under mains so the SEETEC is functioning in some ways.
When the mains power is cut the fault light on the SECTEC flashes 2 times. I can not find a manual that explains if 2 flashes means anything in particular.

I have checked all wiring and can not find any issues. Can anyone suggest any other tests I can or suggest what might be the actual issue?

The SETEC is in a 14.44 expanda connected to 4 12V circuits.
Thanks Brad.
 

Drover

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Nov 7, 2013
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I found on my battery switch while the wires looked like they were connected they actually were only pushed in, not clamped and thusly failed so a physical check not a visual of connections but does sound like a poor connection between Setek and battery.
Do you have anything on the meter from battery at the Setek, thats with 240 disconnected. ??
 

Brad Hardwick

New Member
Oct 19, 2017
9
1
3
12
Vic
Hi All,
This is what I have tested.
  • If I turn off 240V I get 12V on the Battery Terminals on the Setec so the battery is supplying some voltage.
    • This indicates that there is not a fuse or other stopping voltage to/from the battery.
  • If I disconnect the battery and turn on 240V I get 12V on the Battery terminals on the sectec so it is trying to charge the battery.
    • When this occurs the red fault light does not flash on the setec.
    • When I reconnect the battery the red fault light does flash on the setec (twice) what ever that means when I turn off the 240V
  • I have disconnected the battery switch completly. This should force the battery to be always on. As this is a disconnect switch and does not need to be connected. this made no difference.
  • I have checked the main battery fuse as well and it is fine.
Any other tests anyone can suggest would be good?
Is there a way to test if the battery is faulty somehow and causing the flashing?

Cheers BRad.
 

Boots in Action

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Mar 13, 2017
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Hi All,
This is what I have tested.
  • If I turn off 240V I get 12V on the Battery Terminals on the Setec so the battery is supplying some voltage.
    • This indicates that there is not a fuse or other stopping voltage to/from the battery.
  • If I disconnect the battery and turn on 240V I get 12V on the Battery terminals on the sectec so it is trying to charge the battery.
    • When this occurs the red fault light does not flash on the setec.
    • When I reconnect the battery the red fault light does flash on the setec (twice) what ever that means when I turn off the 240V
  • I have disconnected the battery switch completly. This should force the battery to be always on. As this is a disconnect switch and does not need to be connected. this made no difference.
  • I have checked the main battery fuse as well and it is fine.
Any other tests anyone can suggest would be good?
Is there a way to test if the battery is faulty somehow and causing the flashing?

Cheers BRad.

Hi @Brad Hardwick , from what you are describing, I would be checking battery voltage under load. Just because you get 12 volts on battery terminals when charger (Setec) is not connected does not mean that the battery is okay. In fact, if battery is being charged, voltage should be up around the 14 volt mark (even with the Setec ) and battery voltage not under load when charged should be around 12.6 volts. The Setec has a low voltage disconnect of around 11.6 volts (check manual for exact value) and will only charge very slowly (about .8 amp) until voltage gets up to 12.4 ?? (check manual again). If you are also trying to drag power from battery for any load whilst battery is low and Setec is only able to put in a feeble amount of charge, I do not believe too much will happen. If you have a good multimeter, check battery terminal voltage (no load) when Setec 240 volt connected and check that it is above the reading when 240 volt Setec is NOT operating. Another way would be to charge the battery directly with a "smart charger" with the proper battery type selected Gel or AGM (lead acid) and see if it responds to charging. If it does, then battery voltage is so low that Setec is really only trickle charging whilst trying to get battery voltage up to the point where it can safely increase charging rate to 10 or 15 amps (depending on Setec Model). If you do not have a Setec manual, you can download one so you get a better understanding of how things work. @mikerezny has full details of where you can download manual. Hope this helps and that your battery is not stuffed from being left discharged too long or discharged too low too many times. Batteries need to be looked after all the time for best life.
 
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Drover

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As @Boots in Action said also have you set you multimeter up to show your power to 2 decimal places not just auto scan ??? it helps to get a better reading.
.........With the Setek off is the battery reading the same at the Setek terminals as the battery terminal ?????
.........If the voltage isn't the same and it's under 12.4v then pull the battery out and hook up to a smart charger for 24hrs, then once remove charger and check voltage 30 ins later if under 12.6 the battery is cactus more than likely, though a decent smart charger would have shown a fault code earlier.

.........Check continuity at every junction on the cable from battery to Setek, you will be surprised how a bad connection will still show okay until a bit of load is applied.

............I would also give the terminal ends on the cables to the Setek and good wriggle and continuity check with meter as they are not the greatest at fitting terminals and even though it may appear crimped sometimes they aren't giving good contact and require an extra crunch......
 
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mikerezny

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Sep 11, 2016
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Hi Brad,
I am a bit confused. The Setec 35-II does not have a battery switch. The battery switch was added on the series III models.
Can you confirm exactly what model Setec you have?
The model number is usually on a sticker on the inside of the fuse cover on the front panel.

As @Drover and @Boots in Action stated. Reading 12V on your battery gives very little information. In order to work with 12V van systems I would recommend you get hold of a digital voltmeter capable of reading 3 1/2 digits. This means that when set to the 20V scale, you can measure voltages around 12V with 2 digits of accuracy. i.e. 12.11V.

Tracking down these problems can seem daunting at first, but if you have the right test equipment, the correct manual, a methodical approach, some good assistance, and some patience, solving these problems becomes much easier. Especially when you encounter other issues in the future.

All the Sete manuals are available for download from:
http://www.setec.com.au/old__trashed/jayco-customers/

kindest regards
Mike
 
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Drover

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I think you will find @mikerezny that the "Battery Switch" is just a switch added inline between the battery and Setec to enable the circuit to be shut down and isn't an actual part of the Setek unit...................
 

Bellbirdweb

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Jan 24, 2014
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I think you will find @mikerezny that the "Battery Switch" is just a switch added inline between the battery and Setec to enable the circuit to be shut down and isn't an actual part of the Setek unit...................
@Drover on the ST35IIi the battery switch connects to the Setec unit itself and operates a relay in the unit which connects and disconnects the 12v.

Effectively it does pretty much the same thing as an in line switch but it’s a bit more than that.
 

mikerezny

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Hi @Drover,
the wiring of an external battery switch is very much dependent on which version Setec is installed.
On the III version a specific function is provided on the Setec. The battery is disconnected by the Setec III if the switch is closed:

Oops, sorry @Bellbirdweb, I hadn't read your post, stating basically the same as what I have written.

Remote Battery Isolate Switch: The ST-III series power supplies allow for connection to a remotely positioned switch that provides a manual disconnection of the battery from the loads and the main charger. When the switch contacts are closed, the battery will be isolated from the loads.

NOTE: When the battery is isolated from the loads using the battery isolate switch it will NOT charge at the 10/15 A rate even if the mains is connected to the power supply. In this condition it will ONLY charge at the Trickle charge rate.

Setec models before the III do NOT have a battery switch function within the Setec unit. If there is an external battery switch, then, as you stated, it is probably wired between the Setec battery connection and the battery terminal. However, in this case, when the switch contacts are OPEN, the battery would be isolated from the loads. Hence my question as to finding out EXACTLY what model Setec is installed. Also, in this case, isolating the battery would mean that the Setec would also neither charge NOR trickle charge the battery since it is completely disconnected from the Setec unit.

If you have a look at the wiring diagram for the Setec II and Setec III you will easily see what I mean. I have attached the diagrams for both the Setec II and the Setec III below.

cheers
Mike

SETEC II Functional Block Diagram

Setec II.jpg


SETEC III Functional Block Diagram
Setec III.jpg
 
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Drover

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You know a simple " later model Setec unit have a switch incorporated" would do @mikerezny , ....I went back to the start and saw what actual unit it is so I have got back on track, the Setec units don't really impress me at all.
 
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Boots in Action

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Mar 13, 2017
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Hi,
Recently the battery light has stopped turning on my SETEC 35II and when mains power is cut it is not supplying power to the van via the battery. All 12V light etc work under mains so the SEETEC is functioning in some ways.
When the mains power is cut the fault light on the SECTEC flashes 2 times. I can not find a manual that explains if 2 flashes means anything in particular.

I have checked all wiring and can not find any issues. Can anyone suggest any other tests I can or suggest what might be the actual issue?

The SETEC is in a 14.44 expanda connected to 4 12V circuits.
Thanks Brad.

Hello @Brad Hardwick , I have had further thoughts about your problem and have also found my Setec manual. Although my unit is a later model, after reading my manual, I am pretty sure you have a battery problem. Firstly, you have said that you are able to have lighting (12 volt) WHEN THE SETEC IS SUPPLYING POWER TO BATTERY, but that when 240 volt power is disconnected, there is no power for lights (or anything else too I guess!) and the battery fault light flashes . That is an indication that there is insufficient power available for battery to carry any load on its own. The lights etc work when 240 volt from Setec is pushing 12 plus volts from transformer across the high resistance of a very low (or stuffed?) battery but battery cannot supply sufficient power by itself.

How often do you charge the battery when not using it??? And how long since that was done?? And how old is battery - AGM or Gel?? All these things will have an effect on the problem you are now looking at. The only other possibility is MAIN PCB micro controller malfunction which is less likely but possible.

Turn off/disconnect 240 volt power and hook up a "smart charger" onto battery terminals for a couple of days and try again. You may get away with that after a few cycles, but you may not. Check battery voltage is around 12.6 or above after charging and see if battery can carry the lighting load. The Setec will be able to continue charging to maintain battery voltage when reconnected`.
 
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