Brooks Instrument MT3809G - Manual (Page 30)

1-24
Installation and Operation Manual
X-VA-MT3809G-MT3810G-eng
Part Number: 541B182AAG
September, 2013
Models MT3809G & MT3810G
Section 1 Introduction
Alarm wiring diagrams
Refer to Figures 1-7 and 1-8.
Alarm accessories
Amplifier power supply (approved isolated barrier) 1 or 2 channel approved
for intrinsically safe application, remotely mounted, 115 or 230 Vac power.
Single pole with double throw (SPDT) relay standard.
For other configurations, consult factory.
Factory Default Alarm Signal
Measuring plate (also called cam) has been mounted according figure below.
This means that the current consumption is defined as:
≥ 3 mA in case of measuring plate not detected = no alarm signal generated
≤1 mA in case of measuring plate detected = alarm signal generated
In combination with a NAMUR relay as mentioned above, the signal can be
converted by Normally Closed or Normally Open connections.
In combination with PLC / DCS alike system, the mA signals should be
obliged as above since June 2005.
1-5-4 Inductive Alarm Switches
Design Features
* 1 or 2 normally open inductive limit switches
* Optional intrinsically safe power supply/amplifier/relay unit
* For low or high limit signalling/switching
* Front adjustable
Description
One or two electronic limit switches can be installed in the indicator
housing to allow initiation of signalling or switching functions on a preset
flow value. The limit switch operates as a slot initiator that is inductively
actuated by a disc mounted on the pointer shaft. Any flow value can be
used for setting the limit value by sliding the initiator along the indicator
scale. Minimum setting distance between two limit switches is
approximately 40% full scale. The position of the initiator also serves to
visually indicate the set value. Settings can be adjusted by removing the
indicator cover, loosening, moving and re-tightening of the alarm indication
needle, and replacement of the indicator front cover.
Specifications - Inductive Alarm Switches
PPPPPower Supply ower Supply ower Supply ower Supply ower Supply 5 - 25 Vdc: (8 Vdc nominal)
Impedence Impedence Impedence Impedence Impedence - Approximately 1 kohm with cam absent
- Approximately 8 kohm with cam present
Ambien Ambien Ambien Ambien Ambient and Oper t and Oper t and Oper t and Oper t and Operating ating ating ating ating See Table 1-4
TTTTTemper emper emper emper emperatur atur atur atur atureeeee
Electrical Connector Electrical Connector Electrical Connector Electrical Connector Electrical Connector M20 x 1.5 according to ISO
(1/2" NPT , 3/4” NPT (F) or cable gland 8-12 mm optional)