Hello,
I have the problem that the tachometer stops working as soon as the BMS sends the "disable charging" signal via CAN.
We have installed a WS500 on a Balmar alternator. The WS500 is connected to a BMS via CAN. A Victron Cerbo GX is also part of the CAN network.
When the engine is started and the BMS is set to "fully charged," the tachometer works for about 30 seconds, after which no RPM is displayed until the BMS switches back to "charging."
I have tried the following:
- Enabled forced tachometer mode
- Tested various values for TachMinField
- DIP switch 8 is activated
Unfortunately, none of these attempts were successful.
Any ideas?
TX
Andre
I havent had a chance to play with the recent f/w updates but its likely the issue is that you will need to set a minimum output on the alt. to provide enough of a sine wave for your alt to see. Increasing this parameter should help. On some alts it has to go as high as 30%, but start low and increase slowly until you get a reliable tach reading. Do NOT make it higher than it has to be.
TachMinField: Minimum % of field drive that will be applied if TACH MODE is enabled.
and a bit more info from page 68 of the WS500 full manual, release 2.6
Tach Min Field: <WHOLE NUMBER ( 0 à 30 )> This is the % value the PWM will be kept at as the minimum drive when ForceTM (Below) has been enabled. BE VERY CAREFUL with this value as it will set the floor in which the alternator is driven. If that floor is too high, it will prevent the regulator from ‘regulating’, burning out the battery. This is the actual PWM value sent to the field drive; though it is capped at 30%.
Set Tach Min Field = -1 to enable auto-determination. (Note: Disabled, installer must set value manually. -1 will be treated as Disabled (0) )
If a Tach Min Field value is set (any value greater then 0), and TACH-MODE is enabled, the regulator will use this value as a minimal field drive %. Even during the warm-up period. You may have to experiment with this value to get one which matches your system, taking care not to make it too great, as that could cause issues with overcharging of your battery.
Set = 0 (default) to not inject any artificial PWM % min value.
And a special note on Li based installs be very careful with Tach Min Field as incorrect setting will prevent the regulator from fully stopping charging when the battery has reached it target SOC
Thanks Rick.
But as I wrote I have enabled firce tach mode and I tried several values for min field including -1 for automatic detection.
unfortunenately this works only for round about 10s after starting the motor ( when bms says " do not charge", if bms aloows to charge then tacho works)
thanks to omg configurtrion tool I can see the graph and the field starts at 5% for 10s and than it goes to zero
Ok, I found something curios.
force tach mode is "3"
set it to "1" and then saved/download to the WS500, but it does not accept this.
Changing the other settings is no problem.
I am using the OGM configuration tool. maybe there is an update for it?
