一条充油电缆线路安装如图D-12所示,设最小油压Pmin=0.02MPa,最大油压Pmax=0.35MPa(ρ=0.868),储备油压Ps=0.03MPa,问电触点高油压报警整定值为多少?

解:(1)Ph=Pmax-h2P×0.98×10-2
Ph=0.35-8×0.868×0.98×10-2=0.28MPa(2分)
(2)电触点压力表装在低压端终端头时,有
Ph=Pmax-(h1+h2+h3)ρ×0.98×10-2
Ph=0.35-(3.5+8-9)×0.868×0.98×10-2
=0.33MPa(2分)
答:电触点压力表装在高端时,高油压报警值0.28MPa,表在低端时,高油压报警值为0.33MPa。(1分)