Posted By: kbjr
Otis 311 gem - 03/20/19 07:52 PM
I have a 311 gem with a drive flashing !B1A
Also the fault on my service tool says precharge dc low
Can’t find what this means can someone help
Thanks
Posted By: heisenberg
Re: Otis 311 gem - 03/21/19 01:07 AM
After a full power down and reset of the MCSS, does the fault still exist?
Most AC drives charge the DC buss through a resistance of some sort until it reaches a set voltage where the resistance is bypassed to fully charge the buss. Otis calls this precharge and once the parameter M1 pick V PU is reached, the M1 contactors in the drive picks to bypass the resistor and charge the buss all the way.
Posted By: BytownVators
Re: Otis 311 gem - 08/24/22 04:13 PM
Currently dealing with this same issue. I replaced the 4 capacitors as a starting point but to no avail. Any tips?
The drive needs to be sent out for repair.
Posted By: BillS
Re: Otis 311 gem - 08/27/22 04:56 PM
I can get these rebuilt. PM me with pics of data tag for quote.
Posted By: Smitty
Re: Otis 311 gem - 08/29/22 01:11 PM
Access electronics out of Waldorf MD does a good job on these. I have replaced several of these over the years.
301 -645-1733
Posted By: efor
Re: Otis 311 gem - 09/05/22 09:29 AM
!B1A
i need your help to solve this problem
There are almost no parts left on the power floor that we haven't replaced, but the fault continues.