I tried putting a Light & Motion Seca 1800 on my Priority Current, It didn't work

Hasaf

Member
I tried adding an L&M Seca 1800 to my Priority current two ways. For those who don't know, this is a hard-wired light intended for eBikes. It has a wide Vin band of 6-24VDC. It draws a peak of 1.9A at 12VDC.

With that out of the way, I mounted it to the front fender bolt, frankly, it looked really good there, very much like a quality factory set up.

Then came the challenge of powering it. The first thing I did was to open the OEM light. The back unscrews easily and it has an input voltage of 6VDC. The circuit board in the OEM light even has a set of unused Vout contacts with predrilled holes. It looked like it was going to be easy. I soldered the wire from the L&M light to those holes and was ready to test.

Here came the problem. There just isn't enough power going to the headlight to reliably power the L&M. It would turn on, however, it would frequently turn off after a few seconds. Further, any attempt to change modes on the L&M, like using their daylight slow strobe, would shut the light off completely.

I then attempted to remove the OEM light from the equation and, instead of using the Vout contacts on the OEM light, wired directly to the wires feeding into the OEM light with the OEM light disconnected. There still wasn't enough power to reliably use the L&M light

It's a shame. I wanted it to work, but it isn't going to. This post might save someone else the bother of trying.
 

Coolbob

Active Member
I added the Light and Motion Nip and Tuck (now renamed Vis-E combo) headlight and taillight to my bike without any difficulty. The Nip and Tuck draw a tiny bit more amperage than bike's lighting circuit is rated for IF I run the headlight at max (500 Lumen), so I keep it set to Pulse, Medium or Low just to be on the safe side.

1800 lumens is a LOT of light, I'm betting that the Seca 1800 draws too much amperage at 6v for your bike's lighting circuit. The Vis-E combo has a max draw of 0.78A on high power with 12V system, but the draw increases to 1.61A peak current draw on high power with 6V system.

You can test a few things to be sure it's not something else.

I'd start diagnosing the problem by disconnecting the Seca 1800 from the bike and connecting a volt meter to the wires you tapped into to to be sure the bike is suppling a steady 6v.

It's possible you got a bad light, I bought my lights off of eBay so I tested them right away by connecting them to a 9v battery before I installed them. You should be able to test the Seca 1800 in the same way or just connect it to a cordless tool battery or car battery.

I went to Light and Motion's website and could not find the amp draw of the Seca 1800 at 6v, you may need to contact Light and Motion to get that spec. You should also reach out to your e-Bike manufacturer to see what the amperage limit is for the lighting circuit.

Good luck and keep us posted.
 
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Alaskan

Well-Known Member
I added the Light and Motion Nip and Tuck (now renamed Vis-E combo) headlight and taillight to my bike without any difficulty. The Nip and Tuck draw about 1-amp over the limit of my bike's lighting circuit IF I run the headlight at max (500 Lumen), so I keep it set to Pulse, Medium or Low just to be on the safe side.

1800 lumens is a LOT of light, I'm betting that the Seca 1800 draws too much amperage at 6v for your bike's lighting circuit. The Vis-E combo has a max draw of 0.78A on high power with 12V system, but the draw increases to 1.61A peak current draw on high power with 6V system.

You can test a few things to be sure it's not something else.

I'd start diagnosing the problem by disconnecting the Seca 1800 from the bike and connecting a volt meter to the wires you tapped into to to be sure the bike is suppling a steady 6v.

It's possible you got a bad light, I bought my lights off of eBay so I tested them right away by connecting them to a 9v battery before I installed them. You should be able to test the Seca 1800 in the same way or just connect it to a cordless tool battery or car battery.

I went to Light and Motion's website and could not find the amp draw of the Seca 1800 at 6v, you may need to contact Light and Motion to get that spec. You should also reach out to your e-Bike manufacturer to see what the amperage limit is for the lighting circuit.

Good luck and keep us posted.

I added the Light and Motion Nip and Tuck (now renamed Vis-E combo) headlight and taillight to my bike without any difficulty. The Nip and Tuck draw about 1-amp over the limit of my bike's lighting circuit IF I run the headlight at max (500 Lumen), so I keep it set to Pulse, Medium or Low just to be on the safe side.

1800 lumens is a LOT of light, I'm betting that the Seca 1800 draws too much amperage at 6v for your bike's lighting circuit. The Vis-E combo has a max draw of 0.78A on high power with 12V system, but the draw increases to 1.61A peak current draw on high power with 6V system.

You can test a few things to be sure it's not something else.

I'd start diagnosing the problem by disconnecting the Seca 1800 from the bike and connecting a volt meter to the wires you tapped into to to be sure the bike is suppling a steady 6v.

It's possible you got a bad light, I bought my lights off of eBay so I tested them right away by connecting them to a 9v battery before I installed them. You should be able to test the Seca 1800 in the same way or just connect it to a cordless tool battery or car battery.

I went to Light and Motion's website and could not find the amp draw of the Seca 1800 at 6v, you may need to contact Light and Motion to get that spec. You should also reach out to your e-Bike manufacturer to see what the amperage limit is for the lighting circuit.

Good luck and keep us posted.
I had that light on a Bosch powered bike. I removed the stock light, bypassing it. I pulled the cable six inches out of the down tube, cut it, slid a length of heat shrink tubing over the cable, soldered the cable from the Seca directly to the light cable coming from the motor, wrapped each wire with electrical tape, slid the heat shrink in place and stuffed it all back in the down tube...done. The on/off button on the Bosch display worked just fine and the light remembered its last setting when turned back on.
 

Coolbob

Active Member
Well, without any testing and given your experience I'm guessing that the Bosch powered bike could handle the Seca amperage draw better than the Current.
 

Alaskan

Well-Known Member
My point was that wiring through the light might be the issue. I would eliminate that possibility before diving any deeper.