Connect to the relays, Connect to the 4–20 ma outputs, Figure 14 – Hach-Lange HACH 5500 sc SiO2 Installation User Manual
Page 16
Figure 14 Device connection
Connect to the relays
D A N G E R
Electrocution hazard. Do not mix high and low voltage. Make sure that
the relay connections are all high voltage AC or all low voltage DC.
C A U T I O N
Fire hazard. Relay loads must be resistive. Always limit current to the
relays with an external fuse or breaker. Obey the relay ratings in the
Specifications section.
C A U T I O N
Chemical exposure hazard. Obey laboratory safety procedures and
wear all of the personal protective equipment appropriate to the
chemicals that are handled. Refer to the current safety data sheets
(MSDS/SDS) for safety protocols.
N O T I C E
Wire gauge less than 18 AWG is not recommended.
The analyzer contains relays for sample concentration alarms (2x),
analyzer system warning and analyzer system shutdown. Refer to
on page 13 to connect a device (NO = normally
open, COM = common, NC = normally closed).
Connect to the 4–20 mA outputs
Use twisted pair shielded wire for the 4–20 mA output connections.
Connect the shield at the recorder end or the analyzer end. Do not
connect the shield at both ends of the cable. Use of non-shielded cable
can result in radio frequency emission or susceptibility levels higher than
the allowed levels.
Refer to
on page 13 to connect the device.
on page 3 for wiring and load impedance
specifications.
Note: The 4-20 mA outputs cannot be used to provide power to a 2-wire (loop-
powered) transmitter.
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