HYDAC ELECTRONIC HFS 2500, Руководство по эксплуатации, Страница: 28 / 40

Flow switch HFS 2500 with ATEX approval Page 8
Status 2020/05/19 HYDAC ELECTRONIC GMBH Mat. No.: 669884
4.4.4
Electrical connection
The switching contacts used in the instruments are potential free and do not need any supply.
Attention!
Switching contact and unit are matched. After the exchange of a switching contact a
readjustment must be made.
Kindly request the relevant instruction.
Change-over contact SEM-A Normally open contact SEM-E
Lead no. 1 Common
Lead no. 1 Common
Lead no. 2 Normally closed Lead no. 2 Normally open
Lead no. 3 Normally open
4.4.5 Function test
The function test must be made outside the Hazardous Area!
Change-over contact (SEM-A):
The function test is performed with a cable tester and a magnet. If measured between core 1 and 2
of the connecting cable, the cable tester must switch from “conductive” to “nonconductive” when
the magnet is in approximation to the front side of the switch unit. If measured between core 1 and
3 of the connecting cable the action of the cable tester must be reversed. The dielectric resistance
(electrical connections – housing) must be > 10 M
Ω .
Normally-open contact (SEM-E):
The function test is performed with a cable tester and a magnet. If the magnet is in approximation
of the front side of the switch unit the cable tester must indicate “conductive” when the switch is
triggered.
The dielectric resistance (electrical connections – housing) must be > 10 M
Ω .
1
2
1
2 3