OPERATION MANUAL | Integral “High Pressure” Blowdown System |
2.1 Bal ancing the Purge if the Pro cess is in Op er a tion
A.Review the draw ing on page 5.
B.Pro cess must be in a steady state.
C.Dis con nect the HIGH and LOW lines from the trans mit ter. Mea sure the DP from the pro cess with a pressure calibrator or other DP measuringdevice..
D.Record the DP reading. ______________________________
E.Reconnect the HIGH and LOW lines back to the transmitter. Make sure the Purge is operating.
F.Ad just the “HIGH” and “LOW” Purge Bal ance ad just ments on the mount ing plate un til the dis play reading equals the read ing re corded in Step D. See the draw ing on page 5.
2.2Bal ancing the Purge if the Pro cess is not in Op er a tion
A.Review the draw ing on page 5.
B.Ensure that there is no flow in the process. If the flow can not be stopped completely follow the in- struc tions in Sec tion 2.1.
C.At tach the HIGH and LOW lines to flow me ter.
D.Ad just the “HIGH” and “LOW” Purge Bal ance ad just ments on the front panel till the dis play reading equals 0.0000 Inch W.C. See drawing on page 5.
þIMPORTANT: It is rec om mended that a Three Valve Man i fold not be used with an MST2400 which con- tains the Con tin u ous Purge Op tion. Con sult fac tory.
2.3Integral 5 MicronCoalescentFilter
A.The MST2400 with continuous purge comes with an integral 5 mi cron Co ales cent Fil ter. See the Drawing on page 5.
B.The filter is intended as a secondary device. The sup ply air should be reg u lated and fil tered before enteringtheenclosure.
C.The integral filter will turn “RED” as it cleans the air. Replace the fil ter be fore the “RED” reaches the right side, or outlet end.
3. Integral “High Pressure” Blowdown System
The MST2400 can be ordered with an Integral “High Pressure” Blowdown System. This op tion is de- signed to clean out Pitot Av er aging Flow sen sors us ing a blast of “High Pres sure” Air (up to 100 PSIG or 6.9 bar) while holding the last out put sig nal from the MST2400.
The MST2400 is ca pa ble of be ing pro grammed to per form a blowdown se quence any where from ev ery 2 min utes up to once ev ery 24 hours (1440 min utes). The blowdown se quence can also be ac ti vated by a re mote pulse from a DCS or other controller.
A.Specifications:
a.Air Sup ply: Max i mum of 100 PSIG (6.9 bar) . If air sup ply is over 100 PSIG then a reg u la tor must be installed.
b.Voltage: 120 VAC. Op tion con tains in te gral 24VDC power sup ply.
c.Se quence Du ra tion: Approximately 30 sec onds from time sig nal is held till sig nal is re stored.
d.Temperature: Maximum150oF.
e.Programmable intervals: 2 min utes to 1440 min utes (24 hours).
f.Pulse Sig nal from ex ter nal controller: Con tact clo sure for ½ sec ond (500 mil li sec onds).
B.Sequence of Operation
a.The MST2400 be gins the Blowdown se quence by hold ing the last out put sig nal.
b.Valves are ac ti vated to iso late and vent the trans mit ter from the pro cess to pre vent dam age.
c.The Hi & Low pro cess lines are al ter nately blown down for ap prox i mately 11 sec onds each.
d.Valves are au to mat i cally ac ti vated to re store sig nal from pro cess back to MST2400.
C.External Activation Signal
The MST2400 In te gral Blowdown can be ac ti vated by a ½ sec ond ex ter nal contact closure pulse sig- nal. The Blowdown can be con trolled by this sig nal only or in com bi na tion with the in te gralcon trol of the MST2400. The MST2000 must be pro grammed to ac cept this sig nal. Re fer to Pro gramming Pa ram e- ters, Sec tion 8. See Wiring Di a grams in Sec tion 14.
þNote: A 110VAC power source is re quired for the In te gral Blowdown Sys tem. An internal 24VDC power sup ply is fur nished with the Blowdown. DO NOT USE THIS POWER SUPPLY TO POWER THE LOOP SIGNAL.
Brandt Instruments, Inc. | MST2000 Multivariable SMARTFLOW ® Transmitter | Page 9 |
