英国Westlock西锁是世界上著名的阀门位置监控产品制造商。主要产品有：旋转阀门位置监视器、线性阀门位置监视器、阀门定位器、微动开关、位置变送器、接近开关等。
产品在中国石化、电力等领域有着广泛的应用。
WESTLOCK阀门反馈信号开关部分号:
EC2000,AccuTrak2200,AccuTrak2600,AccuTrak3400,AccuTrak4000,AccuTrak4040,4080,AccuTrak9900,9918,E9920,E9881,Micro Switch V3,V5,MAGNUM XT-90,3479,Micro Switch V5J012BB1D,V5B010CB3D,NJ2-V3-N,AccuTrak 2004 AN,TCRMVAZ,2004AN-BY-2DPDT-16PT,2007X-BY-E76
2007X-BY-E183,2085A-2DPDT-CS,2147-BY-00-22AD-000,2249-BY-00-22AD-000,
2402ZSC20709,2402ZSC20714,2640-BY-CS-02AD-000,2640-BY-N-015-02BHP-00,4-20mA ATEX Eexd II CT6,2645-BY-00-2200-000,
2869-00-00-2200-000 2SPDT 2XM202A/24VDC Eex d II CT6,4080-BY-2SPDT,4080-BY-K10,3447ABTN00022ABC-00(2247-BY),722A-BY-M19-FIO-4300-MO,9479-BY-2SPDT,BA-FIS-657/667 30-70,ICoT 5230-NI-E-HK-A-O-B,ICoT 5310I-ISE V B A2BN,PB306-BY00 22AD,
M20 to 1/2NPT-PLUG-069 转换接头,2640-BY-CS-02AD
722A-BY-Q300 西锁-000,(2640-BY-N-015-02BHP-00)
722-BY-M9-FIO-4300
2645-BY-00-2200-000,
2645-BY-00-22AD-000,
2645-BY-CS-22AD-00,