某些规范也允许采用外部操作介质，只要这些操作介质系由几个独立的能源供给，或者只要先导式安全阀载荷是有限的。若采用失能开启原理，依先导式安全阀设计结构不同
阀DHI,DHU,DHO,DKE，换向阀 DH-0432/2 73
DH-0471/A 73方向阀 DH-0471/A 73换向阀 DH-0471/A 73手动方向阀 DH-0471/A 73手动换向阀 DH-0471/A 73
DH-0551/2 73方向阀 DH-0551/2 73换向阀 DH-0551/2 73手动方向阀 DH-0551/2 73手动换向阀 DH-0551/2 73
DH-0831/2/A 73方向阀 DH-0831/2/A 73换向阀 DH-0831/2/A 73手动方向阀 DH-0831/2/A 73手动换向阀 DH-0831/2/A 7DLOH-2C-U
DLOH-2C/WP-UAEXD4D62-G24/L12
AEXD4D62-G24/L15
AEXD4D62-G24/L15
AEXD4D63-G24/L12
AEXD4D63-G24/L15
AEXD4D65-G24/L9
AEXD4D65-S1788-G24/T6
AEXD4Z60A-G24/L15
AEXD4Z60a-G24/T4-S1788
AEXd4Z60a-M165/187-G24/L12
AEXD4Z60A-M165/187-G24/L12
AEXDVPWV4D102-80-TI-G24/L15
AEXDVPWV4D102-80-TI-S1788-G24/T6
AH4D101a/f
AH4D101a/r
AH4D61a/r
AH4Z60a/r
DLOH-3C-U
DHI-0630/2
DHI-0614/A
DHI-0751/2
DHI-0714
DHI-07119
DHI-0751/2P
DHI-0639/O
DHI-0713P
DKE-1611X230AC
DKE-1611X24DC
DKE-1632/2X24DC
DKE-1714X24DC
DKE-1751/2
DPHI-2711/D
DH-0140
DH-0113/BT
DH-0143
DH-0151
E-ME-AC-01F
E-ME-AC-05F
E-MI-AC-01F
E-A-PS-USB/IR
E-MI-AC-IR-01H
DH-0901/2方向阀 DH-0901/2换向阀 DH-0901/2手动方向阀 DH-0901/2手动换向阀 DH-0901/2
DH-0914 73方向阀 DH-0914 73换向阀 DH-0914 73手动方向阀 DH-0914 73手动换向阀 DH-0914 73
DK-1111 50方向阀 DK-1111 50换向阀 DK-1111 50手动方向阀 DK-1111 50手动换向阀 DK-1111 50
DK-1113方向阀 DK-1113换向阀 DK-1113手动方向阀 DK-1113手动换向阀 DK-1113
DK-1114方向阀 DK-1114换向阀 DK-1114手动方向阀 DK-1114手动换向阀 DK-1114
DK-1131 50方
