time lock in dunham-bush chiller? - Refrigeration-Engineer.com forums

lin · #1 26-07-2003, 01:32 AM

There is a dunham-bush 200RT screw chiller. the owner said someone set a time lock in the microcomputer control system, so the machine can't startup again, though it ran well in past weeks.

I have never worked on dunham-bush, so know nothing about it's control system. does it really have a time lock?

calders · #2 26-07-2003, 02:37 AM

hi lin
all dunham bush chillers i have worked on have a 10 minute stop start delay. beit PCX or PC what ever. most large motor manufactures say no more than 4 starts an hour.
also all the D&B i have seen hare a cam timer which is easy to wind on so be carefull but at the end of the day it is up to you
regards calders

lin · #3 27-07-2003, 01:20 AM

does it have holiday setting? I cann't find info. about it at the chinese manual.

D.Evans · #4 09-09-2003, 08:18 PM

It does have a Holiday setting in one of the sub menus, but these are rarely used. However go into the Holiday menu and remove any settings to see if the machine will start. Also have you checked in the Alarms list to see if you have any current alarms.

lin · #5 10-09-2003, 02:01 AM

D.Evans,
thank reply. There isn't any alarm active. It has simple guide for schedule setting in manual, but no holiday. I cann't do anything more without enough info.

D.Evans · #6 23-09-2003, 09:49 PM

Look in the Digital Menu to see if flow switch and unit control inputs say ON . If one of those is OFF the unit will not start.