R
richard feynma
Hi , I am new to the forum not a sparky but Physics background .had to make the decision with a car lift whether to buy an inverter or change to a single phase motor . My lift is a Bradbury 40 series 4 tonne .The motor does not need to reverse as it is gravity that takes it down .Also purely for interest the locks only come into play if the steel ropes go slack eg if the ram fails .
I chose to convert to a single phase motor .( I am not doing the work myself. )I have a reasonable knowledge of single phase but no practical knowledge of 3 Phase .Anyway to the point . Replaced 3 phase 1.85kW with a 2.2Kw capacitor start capacitor run single phase .Made the mistake of connecting it into an industrial socket on a short extension lead which I use for one of my welders. The fuse blew presumably with the surge required to start the motor . Re-connected it to a 32A direct connection lift worked raised about two feet but then stopped . Wouldn't lift again . Smoke coming from the power housing . On investigation the starting capacitor had blown it's top .
I researched extensively before choosing to go single phase .As in all grey areas peoples opinions differed .Usually they are all correct you just have to know the context they are talking about . Some say you definitely need to change some of the 3 phase elements in the control box e.g. the contactor others say with slight modification it isn't necessary .
My question is , would the initial fuse blowing event also have blown the starting capacitor or is there any other reason ( save a faulty capacitor ) that could have caused it ? I have a new starting capacitor and have a direct online starter ordered but once again the opinion is divided on whether the D.O.L .S is essential .Thanks for any advice in advance best regards , Ricky F I should also point out because the lift is gravity down,with no motor direction reversal necessary , it is considered one of the easier 3 phase to single phase conversions .cheers. Haven't quite got the hang of the layout on the page yet .
I chose to convert to a single phase motor .( I am not doing the work myself. )I have a reasonable knowledge of single phase but no practical knowledge of 3 Phase .Anyway to the point . Replaced 3 phase 1.85kW with a 2.2Kw capacitor start capacitor run single phase .Made the mistake of connecting it into an industrial socket on a short extension lead which I use for one of my welders. The fuse blew presumably with the surge required to start the motor . Re-connected it to a 32A direct connection lift worked raised about two feet but then stopped . Wouldn't lift again . Smoke coming from the power housing . On investigation the starting capacitor had blown it's top .
I researched extensively before choosing to go single phase .As in all grey areas peoples opinions differed .Usually they are all correct you just have to know the context they are talking about . Some say you definitely need to change some of the 3 phase elements in the control box e.g. the contactor others say with slight modification it isn't necessary .
My question is , would the initial fuse blowing event also have blown the starting capacitor or is there any other reason ( save a faulty capacitor ) that could have caused it ? I have a new starting capacitor and have a direct online starter ordered but once again the opinion is divided on whether the D.O.L .S is essential .Thanks for any advice in advance best regards , Ricky F I should also point out because the lift is gravity down,with no motor direction reversal necessary , it is considered one of the easier 3 phase to single phase conversions .cheers. Haven't quite got the hang of the layout on the page yet .
