declare @rows int, @err int
select @rows = 1
set rowcount 50000 -- in 50K chunks
begin tran
while @rows > 0
begin
delete from dbo.SensorValueHistory where <Condition>
select @rows = @@rowcount, @err = @@error
commit tran
-- check @err here for non zero, error handling is for wimps ;-) --
if @rows >0
begin tran
end