Warner Electric MCS-208 - Manual (Page 19)

Warner Electric • 800-825-9050 P-276 • 819-9045 19
with the machine stationary. Check that the
“Power” indicators on both the MCS-166
and MCS-208 are illuminated.
 4. Set the front panel “Torque/Span Adjust”
potentiometer to its full CCW positioning.
 5. Brake-off/brake-on switch checks
 a. Set the brake-on switch to its normal
run mode.
 b. Set brake-off switch to off position
and note the transducer pressure.
 c. Return the brake-off switch to its
normal running position.
 d. Place the brake-on switch (if used) in
the brake-on position and note that
the transducer pressure output
increases.
 e. Return the brake-on switch to its
normal running position.
NoTe: If the transducer pressure decreases when
brake-on is activated, the wiring is reversed. Refer to
the MCS-208 wiring section for the proper connections.
 6. Brake Off/Brake On Calibration
NoTe: The MCS-208 is factory calibrated for a 4-20ma
output. Proceed to Step 7, Transducer Calibration, if
the MCS-208 need not be adjusted. If adjustment is
required, refer to Table 2 for the correct values called
out in the adjustment procedure. An accurate voltmeter
is required to set up the system.
Table 2
Y min (Min transducer input)
Y max (Max transducer input)
P sup (supply pressure)
P max (max pressure - brake-on mode)
P cal (max pressure - run mode)
* For current transducers, this value is given in maDC.
For voltage transducers, this value is given in VDC.
** If shop air does not maintain 80 psi minimum, the P
max and P cal should be set lower. P max should be at
least 5 psi lower than the minimum supply pressure. P
sup and P cal should be at least 5 psi less than P max.
 a. With the control power off, set the
meter to measure MCS-208 control
output to the transducer.
 b. Apply power to the system.
 c. Place the brake-off switch in the
brake-off mode.
 d. Set the zero potentiometer on the
control output driver board to Y min.
(Refer to Table 2). Rotate the zero
potentiometer CW to increase and
CCW to decrease the output.
 e. Return the brake-off switch to normal
run mode.
 f. Set the brake-on switch to the brake
on mode.
 g. Set the span potentiometer on the
control output driver board to equal Y
max. Rotate the span pot CW to
increase and CCW to decrease the
output.
 h. Return the brake-on switch to the
normal run mode.
 i. Repeat Steps c-h to make sure the
zero and span potentiometers are
properly set. There is some
interaction between these two
potentiometers.
 7. Transducer Calibration
NoTe: For transducers that are precalibrated for
0-75 psi, calibration is not generally required. If the
transducer is labeled as calibrated for 0-75 psi and is
mounted vertically, proceed to Section C, Input
Calibration. Otherwise proceed with the following
adjustment procedure. The zero and span potentiome-
ters are identified on the outside of the transducer.
Use care when adjusting these potentiometers.
 a. Place the brake-off switch in the
brake-off mode.
 b. If the pressure reads above 0 psig,
turn the zero pot on the transducer
CCW until the pressure just reaches
zero.
Transducer Range
Adjustment 1-5 4-20 10-50 1-5 1-9
Variable (ma DC) (ma DC) (ma DC) (VDC) (VDC)
Y min* 1 4 10 1 1
Y max* 5 20 50 5 9
P sup** (psi) 80 80 80 80 80
P max** (psi) 75 75 75 75 75
P cal** (psi) 70 70 70 70 70