MMS 6110 Direction for use
Purpose and Application Page 3
1.
PURPOSE AND APPLICATION
The MMS 6110 dual-channel shaft vibration monitor is part of the MMS 6000 machine moni-
toring system. In connection with two eddy current measuring chains, the microprocessor
controlled module serves measurement and supervision of relative shaft vibrations at all kind
of turbines, compressors, fans and gear boxes.
During configuration the two channels of the monitor may be defined for separate measure-
ment or for the combined use. The following modes are possible:
• Dual channel mode with two separate channels.
For each channel the configuration parameters (measuring range, type of transducer, limit
values etc.), can be defined separately. Each channel calculates its own characteristical
value (peak-peak or zero-peak value) and checks it on limit exceedings and faults of the
measuring chain.
• Calculation and output of maximum value Smax.
The resulting maximum value Smax of the shaft vibration for the measuring directions X
and Y according to DIN 45670 (characteristical value A) is calculated by geometrical addi-
tion of the actual values S1 (channel 1) and S2 (channel 2) [ )t(2s)t(1s)t(S
22
m
+= ]. The
maximum value Smax is output as characteristical value and checked on limit exceedings
• Calculation and output of maximum vibration amplitudes S
pp
max. according to DIN
45 670, characteristical values B or max (X, Y) according to API 670.
The characteristical value, output and checked on limit exceedings, is formed by the
greatest of the two measuring values of channels 1 or 2 in X and Y-measuring direction.
The characteristical value is output as impressed current of either 0...20 or 4...20 mA.
Additionally, there is an analog output, providing a standardized d.c. output NGL of 0...+10V
proportional to the static distance between sensor and measuring target.
For checking the signals on limit exceedings, there are two alarm channels, each of them
with one warning (Alert) and one danger level. In the dual channel operating mode the char-
acteristical value is supervised by the relevant alarm channel. The limit values for pre alarm
(ALERT) and main alarm (DANGER) may be adjusted separately.
With measuring modes max. value Smax and vibration amplitude S
pp
max resp. max(X,Y) the
characteristical value, calculated from both channels, is supervised by the alarm channels of
both measuring channels - but with only one "Alert" and one "Danger" limit.
During configuration the alarm outputs can be activated and the limit values defined. The
alarm status is shown by two red LEDs on the front of the monitor. The module provides four
relay driver outputs which can alternatively be switched to normally closed or normally open
operation mode.
Input "Alarm blocking" permits blocking of the alarm outputs by means of an external signal.
During configuration, response delay and alarm blocking at fault situations can be defined.
Two green LEDs on the front and two relay driver outputs indicate the status of channel and
monitor supervision. In the normal state, i.e., if neither the channel nor the module super-
vision have detected an error, if the channel measurement is in the settled state and the
alarms are not blocked, message "Channel Clear = OK" will be indicated.
