Emerson daniel 1500 series, User Manual

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1815B Zero crossing preamplifier configuration Table 2-9:
Designator Terminal connections Description
Customer connection 1 Supply voltage
2 Common
3 Output signal (x1)
4 Output signal (x2)
Pickoff (1) 5 White
6 Red
1817X Bi-directional preamplifier configuration Table 2-10:
Designator Terminal connections Description
Customer connection 1 Supply voltage
2 Common
3 Direction Forward (A before B): OVDC, OC
Reverse (B before A): Vs, OC
4 Channel A output
5 Channel B output
6 Optional (X2)
Pickoff (2) 7 White
8 Red
9 White
10 Red
Pickoff coils
The Series 1500 LTM has the capacity for dual pickoff coils mounted 90º electrically out of
phase. Each pickoff produces a low level sine wave signal which varies in amplitude (mV)
and frequency (Hz) proportional to the velocity of the turbine blades. This signal
information is coupled to the input terminals of the preamplifier.
The optional dual LME LTM can be configured with four pickoff coils, each pair mounted
90º electrically out of phase.
Induced interference
The LTM should be located as far as possible from any electrical equipment such as motors,
solenoids or relays which could induce an interference signal into the turbine meter pickoff
coil. High amplitude interference introduced into the preamplifier can result in
interference with the flow signal. Proper shielding and an earth grounded LME housing will
greatly reduce the possibility of induced interference.
Operating conditions and specifications
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