BEKA BA405C, Руководство пользователя

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6.1.6 Over and under-range
The BA405C can display numbers between -
1999 and 1999. If this range is exceeded the three
least significant digits will be blanked. Under-
range is indicated by -1 and over-range by 1.
7. MAINTENANCE
7.1 Fault finding during commissioning
If a BA405C set point station fails to function
during commissioning the following procedure
should be followed:
Symptom Cause Solution
No loop Incorrect Check wiring
current wiring or no and power
power supply supply polarity
BA405C Positive The display has been
displays 1 over-range incorrectly calibrated
& is trying to show a
number greater than
1999.
BA405C Negative The display has been
displays -1 over-range incorrectly calibrated
& is trying to show a
number less than
-1999.
Unstable Insufficient Check that voltage
loop supply between terminals
current voltage 1 & 3 is greater than
6.1V, or 10V between
terminals 1 & 13 if a
loop powered
backlight is fitted.
Unstable Power supply Reduce ripple
display has voltage.
ripple
7.2 Fault finding after commissioning
ENSURE PLANT SAFETY BEFORE
STARTING MAINTENANCE
Live maintenance is permitted on intrinsically
safe equipment installed in a hazardous area,
but only certified test equipment should be
used unless a gas clearance certificate is
available.
If a BA405C fails after it has been functioning
correctly, the following procedure should be
followed:
Symptom Cause Solution
No loop Wiring or power Check wiring
current supply fault and power
supply
Unstable Insufficient Check that voltage
loop supply between terminals
current voltage 1 & 3 is greater than
6.1, or 10V between
terminals 1 & 13 if fitted
with a loop powered
backlight.
Unstable Power supply Reduce ripple
display has developed
voltage ripple
If this procedure does not reveal the cause of the
fault, it is recommended that the BA405C manual
set point station is replaced with a spare
instrument.
7.3 Servicing
We recommend that faulty BA405C set point
stations are returned to BEKA associates or to our
local agent for repair.
7.4 Routine maintenence
The mechanical and electrical condition of the
instrument should be regularly checked. Initially
annual inspections are recommended, but the
inspection frequency should be adjusted to suit the
environmental conditions.
7.5 Guarantee
Set point stations which fail within the guarantee
period should be returned to BEKA associates or
our local agent. It is helpful if a brief description of
the fault symptoms is provided.
7.6 Customer comments
BEKA associates is always pleased to receive
comments from customers about our products and
services. All communications are acknowledged
and whenever possible, suggestions are
implemented.