Danfoss 90 Series Installation Manual

Series 90 Intrinsically Safe Control
Installation, Maintenance
This line of Intrinsically Safe Pressure Control Pilots receives a low current input signal from a variety of machine controllers and
converts the current signal into a proportional di erential pressure signal suitable to control larger hydraulic equipment in hazardous
locations. The Intrinsically Safe Controls can be added to a Series 90 pump as a standard option or purchased separately.
Danfoss o ers five di erent models of Intrinsically Safe Pressure Control Pilots to accommodate a variety of standard industrial
process controllers. Various combinations of hydraulic nozzle sizes and coil resistances yields a relationship between electrical current
(input) and hydraulic di erential pressure (output).
Refer to the Unit Specifications tables on pages three and four for proper selection.
Ensure that the four supplied O-rings are in place on the bottom of the unit. These pressure control pilots are fastened to the second
stage of the control with four M5 x 0.8 x 16 mm socket head screws. Torque to 5 Nm (44 in-lb).
A Mil-Spec Connector (MS3102C-14S-2P) provides the means for electronic signal input to the device. Proper selection of the mating
connector to ensure safe operation in a hazardous environment is required (Recommended MS3108E-14S-S, Danfoss Kit number
K08106). A suppression circuit is incorporated in the PCP torque motor cover but by itself does not insure intrinsic safety. An additional
safety barrier used to connect intrinsically safe circuits with non-intrinsically safe circuits must be connected in series between the
PCP and controller. The safety barrier and electrical controller must be isolated from the hazardous area either through use of a purge
enclosure or mounted in a safe area. The intrinsically safe device enclosure grounding terminal must be connected to a robust chassis
ground. The connection must be in accordance with applicable standards where required.
1
© Danfoss A/S, 202 • •