，发出电信号，使电气元件（如电磁铁、电机、时间继电器、电磁离合器等）动作，使油路卸压、换向，执行元件实现顺序动作，或关闭电动机使系统停止工作，起安全保护作用等。
压力继电器有柱塞式、膜片式、弹簧管式和波纹管式四种结构形式。下面对柱塞式压力继电器的工作原理作一介绍：
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DS T6C 012 1R00 B1 T6C0121R00B1
S T6C 012 1R01 B1 T6C0121R01B1
S T6C 012 1R02 B1 T6C0121R02B1
S T6C 012 1R03 B1 T6C0121R03B1
S T6C 014 1L01 B1 T6C0141L01B1
S T6C 014 1L02 B1 T6C0141L02B1
S T6C 014 1L03 B1 T6C0141L03B1DS5-S11/12N-D24K1
MD1D-SVDC
MD1D-SVAC
DS3-TA/10N
DS5-SA1/12N-D24K1
MD1D-TA/50-24VDC
MD1D-TAVAC MD1D-TA/50-24V-CC
MD1D-SV-CC
MD1D-2TA/50-24V-CC
P2D-M5/32
MD1D-S3/55 MD1D-S1/55
MD1D-TA/55 D4D-S3/50 DS5-S3
MD1D-S4/55 MD1D-S2/53
MD1-TA/55 RM45/MP CRQ
MD1D-S1/50 MD1D-RK/50
DS3-S10/10N DS5-S10/12N-D24K1
MD1D-SVDC MD1D-SVAC DS3-S11/10N DS5-S11/12N-D24K1
MD1D-SVDC MD1D-SVAC DS3-TA/10N DS5-SA1/12N-D24K1
MD1D-TA/50-24VDC MD1D-TAVAC DS3-TC/10N DS5-SB1/12N-D24K1
MD1D-TC/50-24VDC MD1D-TCVA
MD1D-SVAC DS3-S2/10N DS5-S2/12N-D24K1
MD1D-SVDC MD1D-SVAC DS3-S3/1
S T6C 014 1R00 B1 T6C0141R00B1
S T6C 014 1R01 B1 T6C0141R01B1
S T6C 014 1R02 B1 T6C0141R02B1
S T6C 014 1R03 B1 T6C0141R03B1
S T6C 017 1L00 B1 T6C0171L00B1
S T6C 017 1L01 B1 T6C0171L01B1
S T6C 017 1R00 B1 T6C0171R00B1
S T6C 017 1R01 B1 T6C0171R01B1
S T6C 017 1R02 B1 T6C0171R02B1
S T6C 017 1R03 B1 T6C0171R03B1
S T6C 017 1R03 B5 T6C017
DC/G75JOAA6VSX2HA
DD-5
D
D
D
D662-P01JAMF6VSX2-A
D
D
DE
D662Z4310K/P02JXMF6VSX2-A
D
D
D
DK
D
D
D
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DK
D
D
D
DB
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SC Lnbsp;32