Fine Tuning - P-Q Controls 504 Series Operation Manual

OPERATIONS MANUAL MODEL 504 / 514 / 524 /534
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PT- and PT+ : The PT+ and PT- terminals provide 5VDC or 6VDC for the command source (check your
specific part number). These terminals are intended to be connected to a 500 Ohm potentiometer with
180Ω padding resistors connected to each end leg of the potentiometer (refer to drawing).
Auxiliary Outputs: The Auxiliary outputs are protected with a thermal shutdown technique. In the event
of a short circuit, the output will not reset to normal operation unless the short has been removed, and
either the power cycled or the joystick returns to neutral.

Fine Tuning

As received, the board is calibrated for a specific valve or pump. A calibration number is recorded on the
serial number tag. The calibration number identifies the configuration of the adjustable parameters. Use
the model number and calibration number to reorder.
To fine tune the valve operation, several adjustments are provided. These adjustment trimpots may adjust
both the "A" and "B" outputs with one trimpot, or may be adjusted by separate trimpots for more precise
tuning. The specific model number determines what trimpots are provided.
LO (Threshold): The LO should be adjusted first. LO adjusts the output when the board first comes on.
Move the command source to its "just on" position (observe that the LED just turns on). Adjust the LO
trimpot (CW to increase) to obtain slight motion of the function.
HI (Maximum): Adjusts the maximum output to achieve full flow of the valve or pump. Move the
command source to the max position (observe lighted LED). Adjust the HI trimpot (CW to increase) to
obtain maximum desired function speed. Adjust HI CCW to a point where speed just starts to drop; then
turn trimpot CW ½ turn to ensure full utility of the command signal swing and eliminate excess current
delivered to the valve.
MID (Optional): Adjusts the midrange output. Disconnect supply voltage from terminal "HI ENABLE"
to put board in midrange mode. Move command source to max position and adjust MID speed.
NOTE: When the MID circuitry is activated, the proportional current at turn on (LO) will be lower than
that when the HI range electronics are engaged. The drop in current becomes greater as the difference
between the Mid calibration and the HI calibration become greater. The net result is that the operator will
need to move the control handle a little further in order to obtain a low function speed when in the
midrange mode. Choose the Range Dependent LO option to eliminate this occurrence.
RMP (Optional): Ramp is provided to smooth abrupt changes of the command signal. Ramp will adjust
the output duration from threshold to max (accel) and from max output to threshold (decel). Ramp is
factory preset to Off (full CCW) for ease of fine tuning LO and HI. Adjust the RMP trimpot (CW to
increase) to obtain desired accel/decel time.
NOTE: Since the circuitry has delay for both accelerating and decelerating a load, it is important to note
that the only means for stopping the output quickly will be with a switch. The switch should interrupt the
command signal or voltage supply to the board, disconnect the valve coil(s) from the board, or energize a
dump or blocking valve. See applications bulletin 940208J1.DWG for specific instructions.
504Manual.Doc