Watson-Marlow 520DuN IP66/NEMA 4X User Manual
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24.1 RS485 command strings
Command
Parameters
Meaning
nCA
-
Clear LCD display
nCH
-
Home the cursor
nDO
xxxxxxxxxx<,yyyyy>
Set and run one dose of xxxxxxxxxx
tacho pulses, with optional drip of yyyyy
(maximum 11,000) tacho pulses. See
note 1
nTC
-
Clear the cumulative tachometer count
nSP
xxx.x
Set speed to xxx.x rpm
nSI
-
Increment speed by 1rpm
nSD
-
Decrement speed by 1rpm
nGO
-
Start running
nST
-
Stop running
nRC
-
Change direction
nRR
-
Set direction to clockwise
nRL
-
Set direction to counter-clockwise
nRS
-
Return status. See note 2
nRT
-
Return the cumulative tachometer count
nW
[line 1]~[line 2]~
[line 3]~[line 4]@
Display text on 1 to 4 lines with ~ as
the line delimiter. Terminated by the @
character. See note 3
nZY
-
Return 0 for stopped or 1 for running
Note 1
: The correlation between tachometer pulses and motor rotation is fixed
and provides a measurable and absolute way of monitoring the number of rev-
olutions of the gearbox output shaft - 10,982 pulses per revolution. This in turn
allows the count to be equated to the amount of material dispensed - assuming
that the pumphead type and tube size are known.
Note 2
: The status is returned to the sender in the following format: [pump
type] [ml/rev] [pumphead] [tube size] [speed] [CW/CCW] P/N [pump number]
[tacho count] [0/1 (stopped/running)] !
For example: 520Du 15.84 520R 9.6MM 220.0 CW P/N 1 123456789 1 !
Note 3
: If the pump speed is changed subsequently, the pump must display the
screen shown here (example figures only) for 4 seconds before reverting to the
custom display. 1 to 4 lines of text can be written with ~
as the line delimiter and @ as the message end.
i.e., 1W520Du@ and 1W520Du~@ are both valid commands.
Note 4
: In all cases 'n' can be any number from 1 to 32 inclusive, and by excep-
tion the # symbol can be used as an all-drives command; but not with the RS,
RT or ZY commands, as the results would be indeterminate.
