Flintec DAS 72.1 - Manual (Page 40)

C.4.6 Set Zero/Tare and Reset Zero/Tare Commands – SZ, RZ, ST, RT
The following commands allow you to set and reset zero and tare values. The zero set during calibration
remains the ‘true zero’ but new ‘current zero’ can be set using the SZ command. If the SZ command is
issued and accepted then all weight values will then be based on the new ‘current zero’. Please remember
that zero value will be subject to the Zero tracking function if enabled.
If the weight signal is not stable (as defined by the No motion range NR and the No motion time NT) then
both the set zero SZ and set tare ST commands will be disabled.
Also the Set Zero SZ command is not allowed if the new zero value required and the ‘calibration zero’ differ
by more than 2 % of the CM value (maximum allowable value).
See chapter 8 “Legal for trade” applications.
SZ Set Zero
This command sets a new “current zero” which is then the basis of all weight values until further updated
by the zero tracking function, another SZ command or the “reset zero” command RZ. The SZ command will
fail (DAS 72.1 responds with ERR) if the new “current zero” is more than 2% (of the CM value) higher or
lower than the “true zero” set during calibration. The SZ command will also fail if the weight signal is not
stable as defined by the No motion range (NR) and the No motion time (NT). If the weight signal is “stable”,
the response to the IS command (Device Status) will show the “signal stable” bit active and the SZ
command will be accepted (OK). If the “signal stable” bit is not active, the SZ command will be rejected and
the DAS 72.1 will respond with ERR (error).
Master ( PC / PLC ) sends DAS 72.1 responds Result
SZ
¿ OK Set zero performed
The SZ command is issued without any parameters and will return either the OK or ERR response. If the SZ
command is accepted the DAS 72.1 responds with OK and the “zero action performed” bit of the device
status (IS) response will be active.
If the command is acknowledged by the DAS 72.1 with OK, the status bit for Zero (request IS) is set to 1. A
renewed SZ command or the reset zero command [ RZ ] changes the current zero point. The command is
not implemented, if the current measured value is more than ±2% of the maximum display value [ CM ] of
calibrated zero point [ CZ ]. DAS 72.1 response is ERR (error).
RZ Reset Zero Point
This command cancels the SZ command and the zero reading reverts to that set by the CZ command during
calibration.
Master ( PC / PLC ) sends DAS 72.1 responds Result
RZ ¿ OK Zero point CZ active again
The DAS 72.1 responds to the RZ command with either OK or ERR. If OK is returned then the “zero action
performed” bit in the Device Status (IS) response will be set to “0”.
Page 40 Manual DAS 72.1