TSDZ8 48V 750W – safe to run 52V (58.8V fully charged)?

[gordone]

Hi,

I have a Tongsheng TSDZ8 48V 750W mid drive kit and I’m trying to understand the real voltage limits of the controller.

Battery I have:
- 52V (14S5P)
- 13Ah
- Full charge: 58.8V
- BMS: 30A

From what I understand, a 48V system is typically designed for ~54.6V max (13S), so I’m unsure if 58.8V is within safe limits for the stock controller.

Questions:
1. Has anyone here run a TSDZ8 48V on a 52V battery long-term?
2. Does the stock controller tolerate 58.8V, or is it a hard limit around 54–55V?
3. Any known differences between controller versions (that affect max voltage)?
4. Risk level – occasional use vs permanent damage?

I’m not looking to push limits unnecessarily, just want to understand if this is:
- safe
- borderline
- or a bad idea

Any real-world experience appreciated

 

[aga7423]

Hi. Have you tried it yet? I'm curious, because I'm waiting for the same motor, and both of my batteries are 52 volts. On the Varstrom site, they sell it with an optional 52-volt battery. So, I believe, it could work reliably for a long time

 

[gordone]

Hi. Have you tried it yet? I'm curious, because I'm waiting for the same motor, and both of my batteries are 52 volts. On the Varstrom site, they sell it with an optional 52-volt battery. So, I believe, it could work reliably for a long time

Hi,

There was no documentation included with the motor and display, but I figured out how to access the display settings. The battery type was set to 52V, so I concluded that it is supported. I have now used it around 20 times, for about 10 km each time.

 

[LeoSuperMoin]

The tsdz8 supports 36v, 48v and 52v. On screens like the ekd01 you can even see it in the settings.

But it only has battery "protection" with 48v batteries.
with 52v batteries when your battery is close to empty and you try to use too much power it will show e08 and cut off power. Depending on voltage sag of the pack this can be at around 15-20% since it always tries full power.
With 48V batteries it gradually reduces power from the point your battery hits 43,5V and will go to around 200w at 41,5 with a hard cutoff of 40,5V.

On the other hand the 52v battery feels more responsive and causes less heat when riding (even tho it's hard to get the motor to overheat from my experience)

 

[gordone]

The tsdz8 supports 36v, 48v and 52v. On screens like the ekd01 you can even see it in the settings.

But it only has battery "protection" with 48v batteries.
with 52v batteries when your battery is close to empty and you try to use too much power it will show e08 and cut off power. Depending on voltage sag of the pack this can be at around 15-20% since it always tries full power.
With 48V batteries it gradually reduces power from the point your battery hits 43,5V and will go to around 200w at 41,5 with a hard cutoff of 40,5V.

On the other hand the 52v battery feels more responsive and causes less heat when riding (even tho it's hard to get the motor to overheat from my experience)

I guess its the BMS voltage limit that will shutoff the power and not the motor regulator for 52v battery?

 

[LeoSuperMoin]

I guess its the BMS voltage limit that will shutoff the power and not the motor regulator for 52v battery?

the tsdz8 has some kind of regulation. it does it with all 48v batteries i have. my battery bms shuts off at 40V exactly and the tsdz8 disables motor power at 40,5V the screen stays on but there is no power anymore (0W). for a 52v it also has the hard shutoff altough i don't remember the exact voltage. the issue is when it applies it's 1200w of power the voltage sags under the limit and you get e08 and have to restart it. there is no gradual decrease of power until the cutoff. it's full power until the sag becomes to much and it triggers the undervoltage protection of the controller.

 

[gordone]

Ahh I see what is the under voltage limit for 52v battery in the regulator?

Reset and use a lower assist level for coming home than

 

[LeoSuperMoin]

Ahh I see what is the under voltage limit for 52v battery in the regulator?

Reset and use a lower assist level for coming home than

For the 52v one the BMS cuts of at 52v and the tsdz8 controller at 53,5 from the short testing I did today.

 

[aga7423]

For the 52v one the BMS cuts of at 52v and the tsdz8 controller at 53,5 from the short testing I did today.

For NMC cells, 3.6 volts means they have 50% of capacity left. So, for a 52V battery (14S), 3.6V × 14 = 50.4V — that will be 50% left. On the other hand, 53.5 volts on the battery means 53.5 / 14 = 3.82 volts per cell. That’s close to 70% remaining.
That’s too bad if the controller cuts off power at such a strange margin (53.5 Volts).

 

[LeoSuperMoin]

For NMC cells, 3.6 volts means they have 50% of capacity left. So, for a 52V battery (14S), 3.6V × 14 = 50.4V — that will be 50% left. On the other hand, 53.5 volts on the battery means 53.5 / 14 = 3.82 volts per cell. That’s close to 70% remaining.
That’s too bad if the controller cuts off power at such a strange margin (53.5 Volts).

Just realized I got a typo in my last message I meant 42 and 43,5V.

 

[aga7423]

Just realized I got a typo in my last message I meant 42 and 43,5V.

Thanks for the information. 43.5 V is a very satisfying value

 

[rondi7]

Since a 52v battery reaches cutoff so early with the tsdz8 and in the range of a close to full charged 48v battery, what would happen if you changed battery types from 52v TO 48v battery. You'd have to keep an eye on voltage so the 52v bms does not shut down the battery--but being crareful--hopefully you get get back home under power.