Yokogawa digitalYEWFLO (DY) - Manual (Page 39)

INSTALLATION
IM 1F2B4-01-YIA
Page 43
3.3 W
IRING
3.3.1 Cables and wires (analog or pulse output wires only)
The following recommendations should be considered when selecting output wire for YEWFLO, and
installing it in the field.
1)
Use 600 V PVC insulated wire or equivalent.
2) Use shielded wire in areas susceptible to electrical noise.
3) Use wire and cable suitable for the ambient environment, especially temperature and
chemical compatibility.
4) Lay wires as far as possible from electrical noise sources such as large transformers, motors,
and power supplies.
5) When wiring in a vertical position, a drip loop with a drain should be installed in the conduit
so that water does not run down the wire and into the converter housing.
6) We recommend using crimp-on solderless type lugs for the output wire termination.
7) For industrial installations, we recommend using conduit or cable tray to protect wiring from
water or mechanical damage. A rigid steel conduit or flexible metal conduit is acceptable.
8) Safety grounding should meet National Electrical Code Class 3 requirements (resistance to
ground of 100 ohms or less). Ground wires should be 600 V PVC insulated wire.
3.3.2 Analog output, 2-wire type (4-20 mADC)
When configured for analog output, the two instrument output wires also provide power. A DC
power supply (user supplied) is required in the loop. The power supply voltage required is
determined by the total instrument loop resistance including output wires. The permissible resistance
versus required power supply voltage is shown in figures 3.3.1 and 3.3.2.
Note: The field chassis ground and minus (-) power supply terminal are isolated from each other and should
not be connected.
Figure 3.3.1: Wiring Connections (Analog) Remote Converter