Lake Shore Model 642 Electromagnet Power Supply User’s Manual
Service
7-13
7.10.4
Power Supply Connector
The Power Supply connector provides the means to connect a water control valve (24 VAC) and an associated water
flow switch (closed during flow) to protect the Model 642 from loss of water flow. Pins 1 & 2 must be closed for normal
operation. Pins 3 & 4 supply 24 VAC at 1 A for operation of a water control valve.
4
1
Pin Name
1 Flow
Switch
(Com)
2 Flow
Switch
3
Power Supply Water Valve A
4
Power Supply Water Valve B
Figure 7-10. Power Supply Connector Details
7.10.5
RS-232C Serial Interface Connector
This connector provides one of two means of computer interface. Command descriptions are found in Section 5.
9
6
5
1
Model 642 Electromagnet Power Supply
Typical Computers
DE-9P (DTE)
DB-25P (DTE)
DE-9P (DTE)
Pin Description Pin
Description Pin Description
1
NC
2
TD (out)
1
DCD (in)
2
Receive Data (RD in)
3
RD (in)
2
RD (in)
3
Transmit Data (TD out)
4
RTS (out)
3
TD (out)
4
Data Terminal Ready (DTR out)
5
CTS (in)
4
DTR (out)
5 Chassis-common
6
DSR
(in)
5
GND
6
Data Set Ready (DSR in)
7
GND
6
DSR (in)
7
Data Terminal Ready (DTR out) (tied to 4)
8
DCD (in)
7
RTS (out)
8 NC
20
DTR
(out)
8
CTS
(in)
9
NC
22
Ring in (in)
9
Ring in (in)
Figure 7-11. RS232C (DTE) Connector Details
