Meggitt VM600 Hardware Manual

VM600 MPS hardware manual (standard version) MAMPS-HW/E 9 - 37
Edition 17 - February 2018
Buffered (raw) outputs
CONFIGURATION OF MPC4 / IOC4T CARDS
9.6 Buffered (raw) outputs
The IOC4T has four differential outputs providing buffered raw signals. These outputs are:
• RAW 1H (high line) Connector J3, Terminal 9
• RAW 1L (low line) Connector J3, Terminal 10
• RAW 2H (high line) Connector J3, Terminal 11
• RAW 2L (low line) Connector J3, Terminal 12
• RAW 3H (high line) Connector J3, Terminal 13
• RAW 3L (low line) Connector J3, Terminal 14
• RAW 4H (high line) Connector J3, Terminal 15
• RAW 4L (low line) Connector J3, Terminal 16.
The raw signals are derived from the signals coming from the sensors connected to
measurement channels 1 to 4 (connector J1 of the IOC4T card). These buffered signals are
identical to those available on the BNC connectors on the panel of the corresponding MPC4
card.
Refer to the MPC4 machinery protection card data sheet for further specifications.
9.7 DSI control inputs (DB, TM, AR)
These DSI control inputs are normally floating (open circuit).
To activate an input, connect it to the RET terminal (Connector J3, Terminal 8). This closes
the contact.
The input function as follows:
• Danger Bypass (DB) – A closed contact between the DB and RET terminals allows the
operator to inhibit the danger relay outputs.
• Trip Multiply (TM) – When there is a closed contact between the TM and RET terminals,
alarm levels are multiplied by a scale factor (software defined).
When TM is open, the scale factor is not taken into account.
• Alarm Reset (AR) – A closed contact between AR and RET inputs resets (clears) any
latched alarms.
NOTE: An externally generated Alarm Reset (AR) should be an aperiodic pulse-type
signal, that is, it should not be activated continuously.
The discrete signal interface (DSI) inputs (DB, TM and AR) share a common reference/return
with the DC outputs (DC OUT 1, DC OUT 2, DC OUT 3 and DC OUT 4). This common
reference/return is known as RET and is available on Connector J3, Terminal 8
(see 9.1 Definition of screw terminals on the IOC4T card).
NOTE: The common reference/return (RET) signal has a voltage limit of ±2 V and a
current limit of 100 mA.
Accordingly, it is recommended to use galvanic separation between the RET on
the IOC4T card and any circuitry connected to the discrete signal interface (DSI)
inputs if the potential difference between RET and the external circuitry could be
greater than 2 V.
For further information on the Danger Bypass function, see 4.6.5 Danger Bypass function
and for further information on the Direct Trip Multiply function, see 4.6.4 Direct Trip Multiply.

Meggitt VM600 Specifications

General

Brand	Meggitt
Model	VM600
Category	Measuring Instruments
Language	English