General Maintenance; Pump - Teledyne 4700 Serivce Manual

Table 1-2 4700 Connector Pin Functions
Pin Signal Name
15 N/A
16 N/A
a. All voltage measurements are referenced to common ground on pins 2 and 14.
b. This pin is also used as the Serial Data Input for use with PC connections. Cable 69-4704-042 is rec-
ommended instead for a serial data connection. See section 4.3.2.
c. Output from internal driver is current limited to 100 mA maximum. The output between the alarm pin
and ground can drive low-power alarm devices rated for 5 VDC. Control higher-power (>100 mA) de-
vices, or devices with different voltage requirements through a user-supplied relay. See section 3.3.9 to
configure alarm conditions.

1.4 General Maintenance

1.4.1 Pump

Section 1 Introduction and General Guidelines
Sampler
Input/Output Parameters/Comments
N/A Not used
N/A Not used
The following sections describe general inspection and mainte-
nance tasks to be performed on the 4700.
Inspect the pump before each use. Inspections are especially
important when pumping large sample volumes over long dis-
tances or when the sample liquid contains a high percentage of
suspended or abrasive solids. Pumps in need of service might
experience performance problems such as:
• Faulty liquid detection
• Inaccurate sample volumes
• No liquid pumped
• Pump jams
To inspect the pump:
1. Disconnect the power to the sampler to ensure that it will
not attempt to operate the pump.
The sampler has a safety interlock that prevents the pump
from operating when the pump housing band is open. DO
NOT tamper with the pump housing and band. The pump is
extremely powerful. The pump can injure you severely if the
sampler activates the pump while you are working on it.
Remove power from the sampler before opening the pump
housing.
2. Refer to Figure 1-2. Release the latch (H) securing the
metal pump housing band (K).
3. Swing the pump housing band away from the pump hous-
ing.
4. Inspect the following:
a. Pump tube – Look for excessive wear caused by the
pump rollers and for cracks along the sides of the tube.
Cracks might not be apparent unless you flex or
squeeze the tubing. If cracks or excessive wear are evi-
dent, replace the pump tube (Section 1.4.2).
4700 Refrigerated Sampler Service Guide
a
(Continued)
WARNING
1-5