Watts HF scientific 28030, Owner'S Manual

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CLX-XT (28652) Page 12
REV 5 (5/2020)
4.3.5 Remote Standby Connections (Cat #25264)
This option allows the instrument to operate on
special user control software and hardware, where
an external control initiates each cycle. This
control line is called RSI or Remote Standby
Input.
The CLX-XT will indicate the current status on
another line called RSO or Remote Standby
Output. These are a relay contact that is closed
when busy (operating) and open when in standby
mode.
The connections are labeled RSI and RSO. The
RSI has + and – polarity connection associated with it and requires a 24VDC
control signal.
The RSO is simply a relay contact and is not polarized.
The use of this option lowers the relays to one Normally Open connection .
4.3.6 4-20 mA
The 4-20 mA output is driven by a 15 VDC power source and can drive recorder
loads up to 600 ohms. Transformer isolation is provided on the CLX-XT. Do not
run 4-20 mA cables in the same conduit as power. Operation of this output is
covered in section 7.1 Setting the 4-20 mA .
To prevent damage to the instrument, and for general safety ensure that power is
disconnected to the CLX-XT prior to making any connections. Polarities of the
connections are labeled beside this termination on the PC board.
The recommended cable is 22 AWG shielded twisted pair. To prevent ground
loops, connect the shield at either the CLX-XT or at its destination, but not both.
The grey terminal block is removable to assist in making connections.
The 4-20mA is factory calibrated. An adjustment is available on the 4-20mA in
sections 7.13 and 7.14. In addition to making adjustments, these menus output
continuous 4 mA or 20 mA and can be used as a signal test. Remember that the
configuration mode will timeout after 15 minutes.
4.3.7 RS-485/4-20 mA cable Ferrite
To meet IEC requirements for RF radiated immunity a clamp-on type ferrite is
supplied in the accessory kit. It should be placed on the RS-485 or 4-20 mA cable
outside, as close as possible to the CLX-XT. If both outputs will be used, an
additional ferrite will be needed and can be ordered from HF scientific Catalog
number 24560T.