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PV-250 Track Relay Revision History Rev. Date Nature of Revision September 1982 Original Issue March, 2000 Revision Incorporated ECO R-1150. Test and maintenance procedures February 2005 in the manual were updated. Reformatted manual. Corrected resistor values in Figure 3-1; clarified contact block information in April 2005 Figure 4-1;...
PV-250 Track Relay INTRODUCTION This manual covers the PV-250 Plug-In AC Vane Relay used for track circuit applications. Since the relay is a two-element AC vane type, it must be provided with the appropriate equipment to provide the adequate phase displacement between the local and control (track windings).
PV-250 Track Relay 1.3. Specifications This manual provides operating values and parts lists specific to PV-250 Track Relay N342555-809/909. This relay has the following general specifications: 115V Local, 60 Hertz 2F-2B Contacts Local 0.165 Amperes @ 115 Volts The following subsections provide the electrical and mechanical specifications of the PV-250 relays covered in this manual.
PV-250 Track Relay INSTALLATION 2.1. General Relays plug directly into a mounting base that is secured to a rack. The only installation instructions required are for the mounting base. 2.1.1. Care in Handling It is very important that these vane relays be handled carefully so that undue stresses are not applied to the vane structure, which might throw the vane out of adjustment.
PV-250 Track Relay INDEX INDEXING PINS PLATE Figure 2-1. Typical Plug-In Relay and Mounting Base c. The index code for each mounting base is determined by the placement of the holes in the numbered vertical rows of the large white nylon indexing plate that is affixed to the front of the mounting base.
PV-250 Track Relay 2.4. Receptacle Contact Springs 2.4.1. Old-Style Base Only The N434647 mounting base normally will be equipped with the required quantity of J680165 solderless receptacle contact springs and will accommodate one or two #14 or #16 wires. However, it can be equipped with receptacle contact springs for one or two #10 or #12 wires (J680181), or for one or two #18 or #20 wires (J680179).
PV-250 Track Relay Figure 2-2 - Receptacle Contact Springs Installed 2.4.3. Installing Wires in Receptacle Contact Springs Use the following procedure to ensure a good electrical and mechanical connection between the conductor wire and the receptacle contact spring. Table 2-1 identifies the correct crimping tool to be used when installing wires in a receptacle contact spring.
PV-250 Track Relay 5. Remove the crimped receptacle contact spring from the tool and inspect the connection. Make certain that the wire is flush with the crimped barrel and that there are no loose strands of wire. 2.5. Relay Insertion Orient the relay to the mounting base with the name plate right side up;...
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PV-250 Track Relay Copyright 2019 SM 4574F, Rev. 4, March 2019...
PV-250 Track Relay MAINTENANCE This section provides the necessary periodic preventive maintenance procedures that must be performed to ensure continuous, proper, and efficient operation of the PV-250 style relays covered in this manual. This maintenance section covers periodic inspections and performance tests.
PV-250 Track Relay AC Voltmeter (True RMS) Resistor - 1500 ohms, ±10%, 25 watts SPST switch 3.2.2. Shop Calibration Test Procedure NOTE When performing calibration, set local voltage as specified to within ± 1%. When checking relay calibration, current (Amps) readings are to be used. The voltage range shown in the table is for REFERENCE ONLY.
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PV-250 Track Relay 8. Slowly adjust Variac (T1) to decrease the output until all front contacts of the relay open. Record the ammeter A reading; this is the drop-away (DA) current value. It should be within the percentage range, as specified Table 3-1, of the actual pick-up current value measured in Step 6.
PV-250 Track Relay ** The resistance value of R is selected to ensure that when the Variac is set to its Maximum setting the value of current, as measured on meter A, is approx. 10% higher than the maximum Full Stroke current. For the purposes of this test circuit the resistor is fixed, however, it can be a potentiometer and set to a value that permits a 10% higher than the maximum Full Stroke current value.
PV-250 Track Relay ∗ The digital ammeter should be set to display to only three decimal places. Values beyond three decimal place accuracy are insignificant to the calibration and should be ignored. Table 3-2 values are based on ideal phase relations; track volts lead local volts by 90°...
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PV-250 Track Relay Drop Away (DA) Current Value __________ 9. Calculate the DA percentage of actual PU (DA%). It must be equal to or greater than 80% of the actual PU value noted in Step 6. (DA% = Step 8 Value ÷ Step 6 Value ×100).
PV-250 Track Relay Table 3-3. In-Service and Field Calibration Operating Values Current Acceptance Criteria* (Amps) Pick Up (PU) 0.048 Min. – 0.053 Max. Front contacts should be “closed” Full Stroke(FS) Max. 0.053 Min. – 0.059 Max. Vane should touch upper roller Equal to or Greater Than Min.
PV-250 Track Relay 3.4. Shop Maintenance This section provides the information necessary to perform shop level repairs of the PV- 250 style relays covered in this manual. In general, relays arriving at the shop for repair have been checked in the field and have been found to perform unacceptably or have been physically damaged.
PV-250 Track Relay 3.5. Contact Cleaning Procedure 3.5.1. Contacts that are Severely Burned 1. Using a 600-grit emery paper strip, folded with grit side out so that both contacts can be burnished simultaneously, stroke the contacts in the direction of the contact wipe.
PV-250 Track Relay 3.7.1. Recommended Tools and Test Equipment Screw Driver - Torque Measuring Thickness Gauges - 0.001 - 0.060 in. 3.7.2. Vane Removal Dismantle the relay only to the degree necessary to complete repairs. Refer to the appendix for parts information and location. In general, to dismantle the plug-in relay, proceed with the following sequence: 1.
PV-250 Track Relay 10. Move the vane shaft forward and up until the upper back contact heel springs (No. 4 and 5 can be pushed in back of the shaft). Note: The operating arms must be held clear of the heel springs.
PV-250 Track Relay 7. Check to ensure that the operating arms swing freely without any tendency to bind. 3.7.3.2. Operating Arms Installation Procedure 1. Check Operating Arms to see that warpage does not exceed 0.010". Discard any that are warped greater than 0.010".
PV-250 Track Relay Figure 3-3. Method of Closing in of Lower Heel Figure 3-4. Application of Bending Tools 3.7.4. Contact Block Replacement and Adjustment 3.7.4.1. Contact Block Replacement Procedure 1. Remove the old block. 2. Use a small punch to remove the small dowel pins.
PV-250 Track Relay NOTE Replacement contact blocks MUST be of the same general design. 5. Install the dowel pins by carefully tapping them in until they are flush with the aluminum surface. If it is necessary to install a used contact block from another relay, remove only one of the dowel pins from the aluminum frame.
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PV-250 Track Relay 2. Apply a gram scale at the center of the contact tip, on the back contact springs, to just barely move the flexible bronze spring away from the curved stop member. The stop member should be bent if necessary, not the spring, in obtaining this adjustment.
PV-250 Track Relay 6. Check electrical calibration per Section 3.2. 3.7.5.4. Counterweight Adjustment Procedure The values for vane torque given in Table 3-1 refer to the counterweight torque needed to just balance the vane so that the front contacts just barely close when the relay is in the normal mounted position without current in the windings and the case is tapped lightly.
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PV-250 Track Relay 6. Lock the counterweight lock nut securely and spread the end of the screw slightly to prevent the nuts backing off. 3.7.5.5. Inspection for Loose Counterweights and Loose Trunnion Screw Locknuts WARNING The following procedure involves the opening of a vital relay.
PV-250 Track Relay 6. Perform an electrical calibration test in accordance with Section 3.2.2. If the relay passes the In-service/Field Calibration requirements apply glyptal to the exposed threads of the counterweight screw and trunnion locknut, as shown in Figure 3-6.
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PV-250 Track Relay Copyright 2019 SM 4574F, Rev. 4, March 2019 3-19...
PV-250 Track Relay PARTS LIST 4.1. PV-250 Track Relay (N342555-809 and N342555-909) Table 4-1. Parts List for the PV-250 Track Relay, 60 Hz Item No. Description Part No. Frame M433493 Latch Rod M375913 Knob, Knurled J770536 Nut, 1/8 Heavy M395496...
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PV-250 Track Relay Item No. Description Part No. U Roller Bracket M397483 Roller Bracket M161753 Clip, 1/8 x ½, Brass M090506 Lock Bracket M109074 J0498132 Not Used M381123 Washer, Lock #8, SS J047714 Pin, 1/8 steel M381129 Pin, Bronze M232031...
PV-250 Track Relay 4.3. Relay Mounting Base Assembly (N438689-003 and N434647) 4.3.1. New Style Mounting Base (N438689-003) Table 4-4. New Style Mounting Base Parts List Item Description STS USA Part No. Molded Base J780054 Strike, Relay J792848 Nut, Speed Type...
PV-250 Track Relay 4.3.2. Old Style Mounting Base (N434647) Table 4-5. Old Style Mounting Base Parts List Item Description STS USA Part No. Molded Base J776306 Coil Clamping Plate J776318 Contact Clamping Plate J776308 Screw - 6-32 x 3/8 J525061...
PV-250 Track Relay RAIL TEAM AND TECHNICAL SUPPORT The Rapid Action Information Link (RAIL) Team is comprised of a The Rapid Action Information Link Team (RAIL Team) is a group of experienced product and application engineers ready to assist you to resolve any technical issues concerning this product.
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PV-250 Track Relay End of Manual Copyright 2019 SM 4574F, Rev. 4, March 2019...